Urtica dioica (UD), commonly known as “stinging nettle”, is a herbaceous flowering plant that is ... more Urtica dioica (UD), commonly known as “stinging nettle”, is a herbaceous flowering plant that is a widely used agent in traditional medicine worldwide. Several formulations of UD leaf extract have been reported to exhibit anti-inflammatory and antioxidant properties, with anticancer potential. The current study investigated the possible anticancer properties of nettle tea, prepared from Urtica dioica leaves, on acute myeloid leukemia (AML) cell lines, and deciphered the underlying molecular mechanisms. Treatment of AML cell lines (U-937 and KG-1) with UD aqueous leaf extract resulted in a dose- and time-dependent inhibition of proliferation, an increase in apoptotic hallmarks such as phosphatidylserine flipping to the outer membrane leaflet, and DNA fragmentation as revealed by cell-death ELISA and cell-cycle analysis assays. Apoptosis induction in U937 cells involves alterations in the expression of Bax and Bcl-2 upon exposure to nettle tea. Furthermore, the chemical composition of...
Heat shock protein 60 (HSP60) is a mitochondrial chaperone that is implicated in physiological an... more Heat shock protein 60 (HSP60) is a mitochondrial chaperone that is implicated in physiological and pathological processes. For instance, it contributes to protein folding and stability, translocation of mitochondrial proteins, and apoptosis. Variations in the expression levels of HSP60 have been correlated to various diseases and cancers, including hepatocellular carcinoma (HCC). Unlike other HSPs which clearly increase in some cancers, data about HSP60 levels in HCC are controversial and difficult to interpret. In the current review, we summarize and simplify the current knowledge about the role of HSP60 in HCC. In addition, we highlight the possibility of its targeting, using chemical compounds and/or genetic tools for treatment of HCC.
Congenital sucrase-isomaltase deficiency (CSID) is a rare metabolic intestinal disorder with redu... more Congenital sucrase-isomaltase deficiency (CSID) is a rare metabolic intestinal disorder with reduced or absent activity levels of sucrase-isomaltase (SI). Interestingly, the main symptoms of CSID overlap with those in irritable bowel syndrome (IBS), a common functional gastrointestinal disorder with unknown etiology. Recent advances in genetic screening of IBS patients have revealed rare SI gene variants that are associated with IBS. Here, we investigated the biochemical, cellular and functional phenotypes of several of these variants. The data demonstrate that the SI mutants can be categorized into three groups including immature, mature but slowly transported, and finally mature and properly transported but with reduced enzymatic activity. We also identified SI mutant phenotypes that are deficient but generally not as severe as those characterized in CSID patients. The variable effects on the trafficking and function of the mutations analyzed in this study support the view that bo...
A key morphological feature of inflammatory bowel disease (IBD) is the loss of the barrier functi... more A key morphological feature of inflammatory bowel disease (IBD) is the loss of the barrier function of intestinal epithelial cells. The present study investigates endoplasmic reticulum (ER) stress in addition to alterations in protein and membrane trafficking in a dextran sulfate sodium (DSS)-induced IBD-like phenotype of intestinal Caco-2 cells in culture. DSS treatment significantly reduced the transepithelial electric resistance (TEER) and increased the epithelial permeability of Caco-2 cells, without affecting their viability. This was associated with an alteration in the expression levels of inflammatory factors in addition to an increase in the expression of the ER stress protein markers, namely immunoglobulin-binding protein (BiP), C/EBP homologous protein (CHOP), activation transcription factor 4 (ATF4), and X-box binding protein (XBP1). The DSS-induced ER-stress resulted in impaired intracellular trafficking and polarized sorting of sucrase-isomaltase (SI) and dipeptidyl pe...
Background Herbal medicines have been a major target for numerous studies through the past years ... more Background Herbal medicines have been a major target for numerous studies through the past years as an alternative treatment for cancer, mainly due to their minimal effects on normal healthy cells. Annona cherimola, popularly known as Cherimoya, is an edible natural fruit rich in phytochemical components and known to possess various biological activities. Previous studies have reported the anti-cancerous effect of A. cherimola ethanolic leaf extract (AELE) on leukemia. This study aims at studying the potential anti-cancer activity of this extract in vitro in two different breast cancer cell lines, namely MDA-MB-231 and MCF-7, in addition to investigating its toxicity on normal mesenchymal stem cells. Methods The anti-proliferative effect of AELE was evaluated via cell viability assay. Propidium iodide staining, Cell Death Detection ELISA and flow cytometry analysis of Annexin V binding were used to assess cell cycle progression, DNA fragmentation and apoptosis induction, respectivel...
BackgroundColorectal cancer (CRC) is a major public health problem, with almost 1.8 million newly... more BackgroundColorectal cancer (CRC) is a major public health problem, with almost 1.8 million newly diagnosed cases and about 881,000 deaths annually. Chamomile (Matricaria chamomilla) is a well-documented medicinal herb that possesses anti-inflammatory and anti-carcinogenic properties. This study aimed to unravel the effect of aqueous chamomile extract against 1,2-dimethylhydrazine(DMH)-induced CRC in mice.MethodsMale Balb/c mice received a weekly intraperitoneal injection of DMH (20 mg/kg body weight) for 12 weeks. Chamomile extract (150 mg/kg body weight/5 days/week p.o.) was administered at the initiation and post-initiation stages of carcinogenesis. Polyps count, histopathological analysis, real-time polymerase chain reaction (RT-PCR) analysis of Wnt signaling genes, ELISA of cyclooxygenase-2 (COX-2), and enzyme assay for inducible nitric oxide synthase (iNOS) were performed.ResultsChamomile extract modulated the Wnt pathway in colonic tissues, where it significantly downregulate...
Niemann-Pick Type C (NPC) is an autosomal recessive lysosomal storage disease leading to progress... more Niemann-Pick Type C (NPC) is an autosomal recessive lysosomal storage disease leading to progressive neurodegeneration. Mutations in the NPC1 gene, which accounts for 95% of the cases, lead to a defect in intra-lysosomal trafficking of cholesterol and an accumulation of storage material including cholesterol and sphingolipids in the endo-lysosomal system. Symptoms are progressive neurological and visceral deterioration, with variable onset and severity of the disease. This study investigates the influence of two different NPC1 mutations on the biochemical phenotype in fibroblasts isolated from NPC patients in comparison to healthy, wild type (WT) cells. Skin derived fibroblasts were cultured from one patient compound-heterozygous for D874V/D948Y mutations, which presented wild-type like intracellular trafficking of NPC1, and a second patient compound- heterozygous for I1061T/P887L mutations, which exhibited a more severe biochemical phenotype as revealed in the delayed trafficking o...
Malva pseudolavatera Webb & Berthel. is a plant from the Malvaceae family that has long been incl... more Malva pseudolavatera Webb & Berthel. is a plant from the Malvaceae family that has long been included in the human diet due to its various curative effects. Many plant leaf extracts from the various species of Malva genus have been reported to possess anti-cancer properties, however, studies on M. pseudolavatera Webb & Berthel. leaves have documented anti-inflammatory and anti-oxidant effects with no emphasis on their possible anti-cancer potential. The present study explores the anti-cancer properties of Malva pseudolavatera Webb & Berthel. leaf extract on acute myeloid leukemia (AML) cell lines in vitro and deciphers the underlying molecular mechanism. Treatment of AML cell lines with M. pseudolavatera methanolic leaf extract showed a dose- and time-dependent inhibition of proliferation and a dose-dependent increase in apoptotic hallmarks such as an increase in phosphatidylserine on the outer membrane leaflet and membrane leakage in addition to DNA fragmentation. The pro-apoptotic...
Background The edible fruit Annona cherimola has previously shown many nutritional and medicinal ... more Background The edible fruit Annona cherimola has previously shown many nutritional and medicinal properties. The current study evaluates the anti-cancer and anti-proliferative properties of Annona cherimola ethanolic leaf extract (AELE) on Acute Myeloid Leukemia (AML) cell lines cultured in vitro (Monomac-1 and KG-1). Methods The anti-proliferative effect of A. cherimola ethanolic leaf extract was evaluated via cell viability assay. Its pro-apoptotic effect was assessed through Cell Death ELISA and dual Annexin V/PI staining. To further investigate the molecular mechanism by which the extract promoted apoptosis and inhibited the proliferation of the AML cells used, apoptotic protein expression was determined through western blots. Extract composition was elucidated by Gas Chromatography-Mass Spectrometry (GC-MS). Results Our results showed that the treatment with A. cherimola ethanolic leaf extract exhibited an inhibitory effect on the proliferation of both cancer cell lines used in...
Annona cherimola Mill is a large green fruit with black seeds widely known to possess toxic prope... more Annona cherimola Mill is a large green fruit with black seeds widely known to possess toxic properties due to the presence of Annonaceous acetogenins. The present study investigates the anti-cancer properties of an Annona cherimola Mill ethanolic seed extract on Acute Myeloid Leukemia (AML) cell lines in vitro and elucidates the underlying cellular mechanism. The anti-proliferative effects of the extract on various AML cell lines and normal mesenchymal cells (MSCs) were assessed using WST-1 viability reagent. The pro-apoptotic effect of the extract was evaluated using Annexin V/PI staining and Cell Death ELISA. The underlying mechanism was deciphered by analyzing the expression of various proteins using western blots. Treatment with an A. cherimola seed ethanolic extract promotes a dose- and time-dependent inhibition of the proliferation of various AML cell lines, but not MSCs. Positive Annexin V staining, as well as DNA fragmentation, confirm an increase in apoptotic cell death by ...
To cope with the extreme heat stress and drought of the desert, the Arabian camel (Camelus dromed... more To cope with the extreme heat stress and drought of the desert, the Arabian camel (Camelus dromedarius) has developed exceptional physiological and biochemical particularities. Previous reports focused mainly on the physiological features of Arabian camel and neglected its cellular and molecular characteristics. Heat shock proteins are suggested to play a key role in the protein homeostasis and thermotolerance. Therefore, we aim by this review to elucidate the implication of camel HSPs in its physiological adaptation to heat stress and compare them with HSPs in related mammalian species. Correlation of these molecules to the adaptive mechanisms in camel is of special importance to expand our understanding of the overall camel physiology and homeostasis.
Niemann-Pick Type C (NP-C) is an inherited neurovisceral lysosomal storage disease characterized ... more Niemann-Pick Type C (NP-C) is an inherited neurovisceral lysosomal storage disease characterized by a defect in the trafficking of endocytosed cholesterol. In 95% of patients the gene encoding NPC1 is affected. The correlation of the genetic background in NP-C with the clinical phenotype such as, severity and onset of liver dysfunction, ataxia, dystonia and vertical gaze palsy, has not been elucidated at the molecular level. We have designed strategies to investigate the effect of different mutations in the NPC1 gene at the protein and cellular levels. The NPC1 mutants were expressed in mammalian cells and their structural features, maturation pathways and subcellular localization elucidated. Interestingly, three classes of NPC1 mutants could be identified and further characterized. The first group comprised mutants in which the NPC1 protein revealed virtually similar structural features to the wild type species. It was trafficked to the lysosomes and colocalized with the lysosomal protein marker Lamp2. The second class of NPC1 mutants was only partially trafficked to the lysosomes, but predominantly localized to the endoplasmic reticulum (ER). In the third group with the most severe phenotype, NPC1 mutants were entirely retained in the ER, colocalizing with the ER-protein marker calnexin. In conclusion, this study relates NPC1 mutations to the trafficking behavior of the NPC1 mutants along the secretory pathway. The findings are essential for a comprehensive understanding of the pathogenesis of NP-C and propose a mutation-based personalized therapeutical approach. Niemann-Pick Type C disease (NP-C) is caused by a defect in the trafficking of endocytosed cholesterol with sequestration of unesterified cholesterol in lysosomes and late endosomes 1. Other lipids also accumulate with variation between different tissues: cholesterol and sphingomyelin storage is most abundant in peripheral tissues, while glycosphingolipid (GSL) buildup is most significant in the central nervous system 2. NP-C disease can affect the viscera (liver, spleen, and sometimes lung) and central nervous system with most common clinical symptoms (over 70% of cases) being clumsiness, learning difficulties, ataxia, dysphagia, dysarthria and vertical gaze palsy 3. NP-C is caused by an autosomal recessive mutation in one or both of the NPC1 and NPC2 genes, with NPC1 gene mutations being present in 95% of cases 4. The clinical spectrum of NP-C ranges from neonatal potentially fatal liver failure to an adult-onset neurodegenerative disease 1. The incidence of severe NPC1 is approximately 1/92,104 live births and estimated at 1/19,000-1/36,000 for the late-onset NPC1 phenotype 5. Clinical diagnosis is difficult due to the diversity of clinical symptoms and the wide range in age at clinical onset. Staining of cultured fibroblasts from skin biopsies with filipin, a fluorescent sterol binding compound, which detects lipid accumulation in the lysosomes is frequently performed, supplemented by genetic testing 6,7. In recent years, identification of several sensitive plasma biomarkers elevated in NP-C (e.g. cholestane-3β,5α,6β-triol,
Journal of physiology and biochemistry, Jan 7, 2017
The mechanisms by which exendin-4 and selenium exert their antidiabetic actions are still unclear... more The mechanisms by which exendin-4 and selenium exert their antidiabetic actions are still unclear. Here, we investigated the effects of exendin-4 or selenium administration on the expression of glucagon-like peptide-1 receptor (GLP-1R), insulin receptor substrate-1 (IRS-1), and preproinsulin in the pancreas of diabetic rats. Diabetes was induced by streptozotocin administration. Diabetic rats were injected intraperitoneally with 0.03 μg exendin-4/kg body weight/daily or treated with 5 ppm selenium in drinking water for a period of 4 weeks. GLP-1R and IRS-1 levels were decreased while the level of preproinsulin messenger RNA (mRNA) was increased in the pancreas of diabetic untreated rats, as compared to that in control rats. Treatment of diabetic rats with exendin-4 increased protein and mRNA levels of GLP-1R, and IRS-1, and the mRNA level of preproinsulin in the pancreas, as compared to their levels in diabetic untreated rats. Selenium treatment of diabetic rats increased the pancre...
Kefir, a fermented milk product, exhibits anti‑tumoral activity in vivo; yet its mechanism of act... more Kefir, a fermented milk product, exhibits anti‑tumoral activity in vivo; yet its mechanism of action remains elusive. Recent studies have focused on the mechanism of action of kefir on cancer cells in vitro. The current study aims at examining the effect of kefir on cell survival, proliferation, and motility of colorectal cancer (CRC) cells. Kefir's anti‑cancer potential was tested on CRC cell lines, Caco‑2 and HT‑29, through cytotoxicity, proliferation, and apoptotic assays. The expression of certain genes involved in proliferation and apoptosis was measured using reverse transcriptase‑polymerase chain reaction (RT‑PCR) and western blotting. To assess the effect of kefir on cancer metastasis, wound‑healing and time‑lapse movies, in addition to collagen‑based invasion assay, were used. The results show that cell‑free fractions of kefir exhibit an anti‑proliferative effect on Caco‑2 and HT‑29 cells. Analysis of DNA content by flow cytometry revealed the ability of kefir to induce cell cycle arrest at the G1 phase. Kefir was also found to induce apoptosis, as seen by cell death ELISA. Results from RT‑PCR showed that kefir decreases the expression of transforming growth factor α (TGF‑α); and transforming growth factor‑β1 (TGF‑β1) in HT‑29 cells. Western blotting results revealed an upregulation in Bax:Bcl‑2 ratio, confirming the pro‑apoptotic effect of kefir, and an increase in p53 independent‑p21 expression upon kefir treatment. MMP expression was not altered by kefir treatment. Furthermore, results from time‑lapse motility movies, wound‑healing, and invasion assays showed no effect on the motility of colorectal as well as breast (MCF‑7 and MB‑MDA‑231) cancer cells upon kefir treatment. Our data suggest that kefir is able to inhibit the proliferation and induce apoptosis in HT‑29 and Caco‑2 CRC cells, yet it does not exhibit a significant effect on the motility and invasion of these cells in vitro.
Urtica dioica (UD), commonly known as “stinging nettle”, is a herbaceous flowering plant that is ... more Urtica dioica (UD), commonly known as “stinging nettle”, is a herbaceous flowering plant that is a widely used agent in traditional medicine worldwide. Several formulations of UD leaf extract have been reported to exhibit anti-inflammatory and antioxidant properties, with anticancer potential. The current study investigated the possible anticancer properties of nettle tea, prepared from Urtica dioica leaves, on acute myeloid leukemia (AML) cell lines, and deciphered the underlying molecular mechanisms. Treatment of AML cell lines (U-937 and KG-1) with UD aqueous leaf extract resulted in a dose- and time-dependent inhibition of proliferation, an increase in apoptotic hallmarks such as phosphatidylserine flipping to the outer membrane leaflet, and DNA fragmentation as revealed by cell-death ELISA and cell-cycle analysis assays. Apoptosis induction in U937 cells involves alterations in the expression of Bax and Bcl-2 upon exposure to nettle tea. Furthermore, the chemical composition of...
Heat shock protein 60 (HSP60) is a mitochondrial chaperone that is implicated in physiological an... more Heat shock protein 60 (HSP60) is a mitochondrial chaperone that is implicated in physiological and pathological processes. For instance, it contributes to protein folding and stability, translocation of mitochondrial proteins, and apoptosis. Variations in the expression levels of HSP60 have been correlated to various diseases and cancers, including hepatocellular carcinoma (HCC). Unlike other HSPs which clearly increase in some cancers, data about HSP60 levels in HCC are controversial and difficult to interpret. In the current review, we summarize and simplify the current knowledge about the role of HSP60 in HCC. In addition, we highlight the possibility of its targeting, using chemical compounds and/or genetic tools for treatment of HCC.
Congenital sucrase-isomaltase deficiency (CSID) is a rare metabolic intestinal disorder with redu... more Congenital sucrase-isomaltase deficiency (CSID) is a rare metabolic intestinal disorder with reduced or absent activity levels of sucrase-isomaltase (SI). Interestingly, the main symptoms of CSID overlap with those in irritable bowel syndrome (IBS), a common functional gastrointestinal disorder with unknown etiology. Recent advances in genetic screening of IBS patients have revealed rare SI gene variants that are associated with IBS. Here, we investigated the biochemical, cellular and functional phenotypes of several of these variants. The data demonstrate that the SI mutants can be categorized into three groups including immature, mature but slowly transported, and finally mature and properly transported but with reduced enzymatic activity. We also identified SI mutant phenotypes that are deficient but generally not as severe as those characterized in CSID patients. The variable effects on the trafficking and function of the mutations analyzed in this study support the view that bo...
A key morphological feature of inflammatory bowel disease (IBD) is the loss of the barrier functi... more A key morphological feature of inflammatory bowel disease (IBD) is the loss of the barrier function of intestinal epithelial cells. The present study investigates endoplasmic reticulum (ER) stress in addition to alterations in protein and membrane trafficking in a dextran sulfate sodium (DSS)-induced IBD-like phenotype of intestinal Caco-2 cells in culture. DSS treatment significantly reduced the transepithelial electric resistance (TEER) and increased the epithelial permeability of Caco-2 cells, without affecting their viability. This was associated with an alteration in the expression levels of inflammatory factors in addition to an increase in the expression of the ER stress protein markers, namely immunoglobulin-binding protein (BiP), C/EBP homologous protein (CHOP), activation transcription factor 4 (ATF4), and X-box binding protein (XBP1). The DSS-induced ER-stress resulted in impaired intracellular trafficking and polarized sorting of sucrase-isomaltase (SI) and dipeptidyl pe...
Background Herbal medicines have been a major target for numerous studies through the past years ... more Background Herbal medicines have been a major target for numerous studies through the past years as an alternative treatment for cancer, mainly due to their minimal effects on normal healthy cells. Annona cherimola, popularly known as Cherimoya, is an edible natural fruit rich in phytochemical components and known to possess various biological activities. Previous studies have reported the anti-cancerous effect of A. cherimola ethanolic leaf extract (AELE) on leukemia. This study aims at studying the potential anti-cancer activity of this extract in vitro in two different breast cancer cell lines, namely MDA-MB-231 and MCF-7, in addition to investigating its toxicity on normal mesenchymal stem cells. Methods The anti-proliferative effect of AELE was evaluated via cell viability assay. Propidium iodide staining, Cell Death Detection ELISA and flow cytometry analysis of Annexin V binding were used to assess cell cycle progression, DNA fragmentation and apoptosis induction, respectivel...
BackgroundColorectal cancer (CRC) is a major public health problem, with almost 1.8 million newly... more BackgroundColorectal cancer (CRC) is a major public health problem, with almost 1.8 million newly diagnosed cases and about 881,000 deaths annually. Chamomile (Matricaria chamomilla) is a well-documented medicinal herb that possesses anti-inflammatory and anti-carcinogenic properties. This study aimed to unravel the effect of aqueous chamomile extract against 1,2-dimethylhydrazine(DMH)-induced CRC in mice.MethodsMale Balb/c mice received a weekly intraperitoneal injection of DMH (20 mg/kg body weight) for 12 weeks. Chamomile extract (150 mg/kg body weight/5 days/week p.o.) was administered at the initiation and post-initiation stages of carcinogenesis. Polyps count, histopathological analysis, real-time polymerase chain reaction (RT-PCR) analysis of Wnt signaling genes, ELISA of cyclooxygenase-2 (COX-2), and enzyme assay for inducible nitric oxide synthase (iNOS) were performed.ResultsChamomile extract modulated the Wnt pathway in colonic tissues, where it significantly downregulate...
Niemann-Pick Type C (NPC) is an autosomal recessive lysosomal storage disease leading to progress... more Niemann-Pick Type C (NPC) is an autosomal recessive lysosomal storage disease leading to progressive neurodegeneration. Mutations in the NPC1 gene, which accounts for 95% of the cases, lead to a defect in intra-lysosomal trafficking of cholesterol and an accumulation of storage material including cholesterol and sphingolipids in the endo-lysosomal system. Symptoms are progressive neurological and visceral deterioration, with variable onset and severity of the disease. This study investigates the influence of two different NPC1 mutations on the biochemical phenotype in fibroblasts isolated from NPC patients in comparison to healthy, wild type (WT) cells. Skin derived fibroblasts were cultured from one patient compound-heterozygous for D874V/D948Y mutations, which presented wild-type like intracellular trafficking of NPC1, and a second patient compound- heterozygous for I1061T/P887L mutations, which exhibited a more severe biochemical phenotype as revealed in the delayed trafficking o...
Malva pseudolavatera Webb & Berthel. is a plant from the Malvaceae family that has long been incl... more Malva pseudolavatera Webb & Berthel. is a plant from the Malvaceae family that has long been included in the human diet due to its various curative effects. Many plant leaf extracts from the various species of Malva genus have been reported to possess anti-cancer properties, however, studies on M. pseudolavatera Webb & Berthel. leaves have documented anti-inflammatory and anti-oxidant effects with no emphasis on their possible anti-cancer potential. The present study explores the anti-cancer properties of Malva pseudolavatera Webb & Berthel. leaf extract on acute myeloid leukemia (AML) cell lines in vitro and deciphers the underlying molecular mechanism. Treatment of AML cell lines with M. pseudolavatera methanolic leaf extract showed a dose- and time-dependent inhibition of proliferation and a dose-dependent increase in apoptotic hallmarks such as an increase in phosphatidylserine on the outer membrane leaflet and membrane leakage in addition to DNA fragmentation. The pro-apoptotic...
Background The edible fruit Annona cherimola has previously shown many nutritional and medicinal ... more Background The edible fruit Annona cherimola has previously shown many nutritional and medicinal properties. The current study evaluates the anti-cancer and anti-proliferative properties of Annona cherimola ethanolic leaf extract (AELE) on Acute Myeloid Leukemia (AML) cell lines cultured in vitro (Monomac-1 and KG-1). Methods The anti-proliferative effect of A. cherimola ethanolic leaf extract was evaluated via cell viability assay. Its pro-apoptotic effect was assessed through Cell Death ELISA and dual Annexin V/PI staining. To further investigate the molecular mechanism by which the extract promoted apoptosis and inhibited the proliferation of the AML cells used, apoptotic protein expression was determined through western blots. Extract composition was elucidated by Gas Chromatography-Mass Spectrometry (GC-MS). Results Our results showed that the treatment with A. cherimola ethanolic leaf extract exhibited an inhibitory effect on the proliferation of both cancer cell lines used in...
Annona cherimola Mill is a large green fruit with black seeds widely known to possess toxic prope... more Annona cherimola Mill is a large green fruit with black seeds widely known to possess toxic properties due to the presence of Annonaceous acetogenins. The present study investigates the anti-cancer properties of an Annona cherimola Mill ethanolic seed extract on Acute Myeloid Leukemia (AML) cell lines in vitro and elucidates the underlying cellular mechanism. The anti-proliferative effects of the extract on various AML cell lines and normal mesenchymal cells (MSCs) were assessed using WST-1 viability reagent. The pro-apoptotic effect of the extract was evaluated using Annexin V/PI staining and Cell Death ELISA. The underlying mechanism was deciphered by analyzing the expression of various proteins using western blots. Treatment with an A. cherimola seed ethanolic extract promotes a dose- and time-dependent inhibition of the proliferation of various AML cell lines, but not MSCs. Positive Annexin V staining, as well as DNA fragmentation, confirm an increase in apoptotic cell death by ...
To cope with the extreme heat stress and drought of the desert, the Arabian camel (Camelus dromed... more To cope with the extreme heat stress and drought of the desert, the Arabian camel (Camelus dromedarius) has developed exceptional physiological and biochemical particularities. Previous reports focused mainly on the physiological features of Arabian camel and neglected its cellular and molecular characteristics. Heat shock proteins are suggested to play a key role in the protein homeostasis and thermotolerance. Therefore, we aim by this review to elucidate the implication of camel HSPs in its physiological adaptation to heat stress and compare them with HSPs in related mammalian species. Correlation of these molecules to the adaptive mechanisms in camel is of special importance to expand our understanding of the overall camel physiology and homeostasis.
Niemann-Pick Type C (NP-C) is an inherited neurovisceral lysosomal storage disease characterized ... more Niemann-Pick Type C (NP-C) is an inherited neurovisceral lysosomal storage disease characterized by a defect in the trafficking of endocytosed cholesterol. In 95% of patients the gene encoding NPC1 is affected. The correlation of the genetic background in NP-C with the clinical phenotype such as, severity and onset of liver dysfunction, ataxia, dystonia and vertical gaze palsy, has not been elucidated at the molecular level. We have designed strategies to investigate the effect of different mutations in the NPC1 gene at the protein and cellular levels. The NPC1 mutants were expressed in mammalian cells and their structural features, maturation pathways and subcellular localization elucidated. Interestingly, three classes of NPC1 mutants could be identified and further characterized. The first group comprised mutants in which the NPC1 protein revealed virtually similar structural features to the wild type species. It was trafficked to the lysosomes and colocalized with the lysosomal protein marker Lamp2. The second class of NPC1 mutants was only partially trafficked to the lysosomes, but predominantly localized to the endoplasmic reticulum (ER). In the third group with the most severe phenotype, NPC1 mutants were entirely retained in the ER, colocalizing with the ER-protein marker calnexin. In conclusion, this study relates NPC1 mutations to the trafficking behavior of the NPC1 mutants along the secretory pathway. The findings are essential for a comprehensive understanding of the pathogenesis of NP-C and propose a mutation-based personalized therapeutical approach. Niemann-Pick Type C disease (NP-C) is caused by a defect in the trafficking of endocytosed cholesterol with sequestration of unesterified cholesterol in lysosomes and late endosomes 1. Other lipids also accumulate with variation between different tissues: cholesterol and sphingomyelin storage is most abundant in peripheral tissues, while glycosphingolipid (GSL) buildup is most significant in the central nervous system 2. NP-C disease can affect the viscera (liver, spleen, and sometimes lung) and central nervous system with most common clinical symptoms (over 70% of cases) being clumsiness, learning difficulties, ataxia, dysphagia, dysarthria and vertical gaze palsy 3. NP-C is caused by an autosomal recessive mutation in one or both of the NPC1 and NPC2 genes, with NPC1 gene mutations being present in 95% of cases 4. The clinical spectrum of NP-C ranges from neonatal potentially fatal liver failure to an adult-onset neurodegenerative disease 1. The incidence of severe NPC1 is approximately 1/92,104 live births and estimated at 1/19,000-1/36,000 for the late-onset NPC1 phenotype 5. Clinical diagnosis is difficult due to the diversity of clinical symptoms and the wide range in age at clinical onset. Staining of cultured fibroblasts from skin biopsies with filipin, a fluorescent sterol binding compound, which detects lipid accumulation in the lysosomes is frequently performed, supplemented by genetic testing 6,7. In recent years, identification of several sensitive plasma biomarkers elevated in NP-C (e.g. cholestane-3β,5α,6β-triol,
Journal of physiology and biochemistry, Jan 7, 2017
The mechanisms by which exendin-4 and selenium exert their antidiabetic actions are still unclear... more The mechanisms by which exendin-4 and selenium exert their antidiabetic actions are still unclear. Here, we investigated the effects of exendin-4 or selenium administration on the expression of glucagon-like peptide-1 receptor (GLP-1R), insulin receptor substrate-1 (IRS-1), and preproinsulin in the pancreas of diabetic rats. Diabetes was induced by streptozotocin administration. Diabetic rats were injected intraperitoneally with 0.03 μg exendin-4/kg body weight/daily or treated with 5 ppm selenium in drinking water for a period of 4 weeks. GLP-1R and IRS-1 levels were decreased while the level of preproinsulin messenger RNA (mRNA) was increased in the pancreas of diabetic untreated rats, as compared to that in control rats. Treatment of diabetic rats with exendin-4 increased protein and mRNA levels of GLP-1R, and IRS-1, and the mRNA level of preproinsulin in the pancreas, as compared to their levels in diabetic untreated rats. Selenium treatment of diabetic rats increased the pancre...
Kefir, a fermented milk product, exhibits anti‑tumoral activity in vivo; yet its mechanism of act... more Kefir, a fermented milk product, exhibits anti‑tumoral activity in vivo; yet its mechanism of action remains elusive. Recent studies have focused on the mechanism of action of kefir on cancer cells in vitro. The current study aims at examining the effect of kefir on cell survival, proliferation, and motility of colorectal cancer (CRC) cells. Kefir's anti‑cancer potential was tested on CRC cell lines, Caco‑2 and HT‑29, through cytotoxicity, proliferation, and apoptotic assays. The expression of certain genes involved in proliferation and apoptosis was measured using reverse transcriptase‑polymerase chain reaction (RT‑PCR) and western blotting. To assess the effect of kefir on cancer metastasis, wound‑healing and time‑lapse movies, in addition to collagen‑based invasion assay, were used. The results show that cell‑free fractions of kefir exhibit an anti‑proliferative effect on Caco‑2 and HT‑29 cells. Analysis of DNA content by flow cytometry revealed the ability of kefir to induce cell cycle arrest at the G1 phase. Kefir was also found to induce apoptosis, as seen by cell death ELISA. Results from RT‑PCR showed that kefir decreases the expression of transforming growth factor α (TGF‑α); and transforming growth factor‑β1 (TGF‑β1) in HT‑29 cells. Western blotting results revealed an upregulation in Bax:Bcl‑2 ratio, confirming the pro‑apoptotic effect of kefir, and an increase in p53 independent‑p21 expression upon kefir treatment. MMP expression was not altered by kefir treatment. Furthermore, results from time‑lapse motility movies, wound‑healing, and invasion assays showed no effect on the motility of colorectal as well as breast (MCF‑7 and MB‑MDA‑231) cancer cells upon kefir treatment. Our data suggest that kefir is able to inhibit the proliferation and induce apoptosis in HT‑29 and Caco‑2 CRC cells, yet it does not exhibit a significant effect on the motility and invasion of these cells in vitro.
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