Induction of liver fibrosis by CCl4 mediates pathological alterations in the spleen and lymph nodes: The potential therapeutic role of propolis.

In an animal models, carbon tetrachloride (CCl4) is a carcinogenic agent that causes liver fibrosis. The current study aims to investigate whether induction in liver-fibrosis by CCl4 in the mouse model could promote the initiation of fibrosis in lymph node and spleen due to sustained increase of inflammatory signals and also aimed to clarify the protective therapeutic effects of propolis. The male mice (BALB/c) were categorized into three experimental sets and each group involved 15 mice. Control group falls into first group; group-II and group-III were injected with CCl4 to induce liver-fibrosis and oral supplementation with propolis was provided in group-III for 4-weeks. A major improvement with hepatic collagen and α-smooth muscle actin (α-SMA) production was aligned with the activation of liver fibrosis from CCl4. Mice treated with CCl4 exhibited collagen deposition towards liver sections, pathological alterations in spleen and lymph node architectures, and a significantly increase the circulation of both T&B cells in secondary lymphoid organs. Mechanically, the secondary lymphoid organs treated with CCl4 in mice exposed a positive growth in α-SMA and collagen expression, increased in proinflammatory cytokine levels and a significant increase in TGF-ß, NO and ROS levels. A manifest intensification in the expression of Nrf2, COX-2, and eNOS and upregulation of ASK1 and P38 phosphorylation. Interestingly, addition of propolis-treated CCl4 mice, substantially suppressed deposition of liver collagen, repealed inflammatory signals and resorted CCl4-mediated alterations in signaling cascades, thereby repairing the architectures of the secondary lymphoid organs. Our findings revealed benefits of propolis against fibrotic complications and enhancing secondary lymphoid organ architecture.

The Therapeutic Mechanisms of Propolis Against CCl4 -Mediated Liver Injury by Mediating Apoptosis of Activated Hepatic Stellate Cells and Improving the Hepatic Architecture through PI3K/AKT/mTOR, TGF-ß/Smad2, Bcl2/BAX/P53 and iNOS Signaling Pathways.

BACKGROUND/AIMS: Propolis is one of the most promising natural products, exhibiting not only therapeutic but also prophylactic actions. Propolis has several biological and pharmacological properties, including hepatoprotective activities. The present study aimed to investigate the underlying molecular mechanisms of propolis against CCl4-mediated liver fibrosis. METHODS: Three groups of male BALB/c mice (n=15/ group) were used: group 1 comprised control mice; groups 2 and 3 were injected with CCl4 for the induction of liver fibrosis. Group 3 was then orally supplemented with propolis (100 mg/kg body weight) for four weeks. Different techniques were used to monitor the antifibrotic effects of propolis, including histopathological investigations using H&E, Masson's trichrome and Sirius red staining; Western blotting; flow cytometry; and ELISA. RESULTS: We found that the induction of liver fibrosis by CCl4 was associated with a significant increase in hepatic collagen and α-smooth muscle actin (α-SMA) expression. Moreover, CCl4-treated mice also exhibited histopathological alterations in the liver architecture. Additionally, the liver of CCl4-treated mice exhibited a marked increase in proinflammatory signals, such as increased expression of HSP70 and increased levels of proinflammatory cytokines and ROS. Mechanistically, the liver of CCl4-treated mice exhibited a significant increase in the phosphorylation of AKT and mTOR; upregulation of the expression of BAX and cytochrome C; downregulation of the expression of Bcl2; a significant elevation in the levels of TGF-ß followed by increased phosphorylation of SMAD2; and a marked increase in the expression of P53 and iNOS. Interestingly, oral supplementation of CCl4-treated mice with propolis significantly abolished hepatic collagen deposition, abrogated inflammatory signals and oxidative stress, restored CCl4-mediated alterations in the signaling cascades, and hence repaired the hepatic architecture nearly to the normal architecture observed in the control mice. CONCLUSION: Our findings revealed the therapeutic potential and the underlying mechanisms of propolis against liver fibrosis.

Camel whey protein protects lymphocytes from apoptosis via the PI3K-AKT, NF-κB, ATF-3, and HSP-70 signaling pathways in heat-stressed male mice.

Heat stress (HS) is an environmental factor that depresses the immune systems that mediate dysfunctional immune cells. Camel whey protein (CWP) can scavenge free radicals and enhance immunity. This study investigated the impact of dietary supplementation with CWP on immune dysfunction induced by exposure to HS. Male mice (n = 45) were distributed among 3 groups: control group; HS group; and HS mice that were orally administered CWP (HS + CWP group). The HS group exhibited elevated levels of reactive oxygen species (ROS) and pro-inflammatory cytokines (interleukin (IL)-1ß, IL-6, tumor necrosis factor-α) as well as a significant reduction in the IL-2 and IL-4 levels. Exposure to HS resulted in impaired phosphorylation of AKT and IκB-α (nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha); increased expression of activating transcription factor 3 (ATF-3) and 70 kDa heat shock proteins (HSP70); and aberrant distribution of CD3+ T cells and CD20+ B cells in the thymus and spleen. Interestingly, HS mice treated with CWP presented significantly restored levels of reactive oxygen species and pro-inflammatory cytokines near the levels observed in the control mice. Furthermore, supplementation of HS mice with CWP enhanced the phosphorylation of AKT and IκB-α; attenuated the expression of ATF-3, HSP70, and HSP90; and improved T and B cell distributions in the thymus and spleen. Our findings reveal a potential immunomodulatory effect of CWP in attenuating immune dysfunction induced by exposure to thermal stress.

Camel Whey Protein Protects B and T Cells from Apoptosis by Suppressing Activating Transcription Factor-3 (ATF-3)-Mediated Oxidative Stress and Enhancing Phosphorylation of AKT and IκB-α in Type I Diabetic Mice.

BACKGROUND: Diabetes mellitus (DM) is associated with severe immune system complications. Camel whey protein (CWP) decreases free radicals (ROS) and modulates immune functions, but its effect on DM-impaired immune systems has not been studied. We investigated the impact of CWP on the immune system in a Type 1 diabetes mouse model. METHODS: Three experimental groups were used: (1) non-diabetic control; (2) diabetic; and (3) CWP-treated diabetic mice. RESULTS: Induction of diabetes by streptozotocin was associated with reduction of body weight and insulin level, increase in glucose level and pro-inflammatory cytokines (IL-1ß, IL-6, and TNF-α), and reduction in IL-2 and IL-4 levels. Upregulated ATF-3 expression was followed by a marked elevation in ROS levels. Lymphocytes from diabetic mice exhibited increased apoptosis through decreased phosphorylation of AKT and IκB-α, increased infiltration of T cells in the spleen and thymus, and decreased B cell numbers in the spleen. Supplementation with CWP decreased the levels of proinflammatory cytokines, ROS, and ATF-3 expression, and increased the levels of IL-4. Treatment with CWP decreased apoptosis by enhancing the phosphorylation of AKT and IκB-α as well as T-cell and B-cell distribution in the spleen and thymus. CONCLUSIONS: Our findings suggest the beneficial effects of CWP supplementation during diabetes on decreasing and orchestrating the redox status and subsequently rescuing the immune cells from exhaustion.

Camel whey protein improves oxidative stress and histopathological alterations in lymphoid organs through Bcl-XL/Bax expression in a streptozotocin-induced type 1 diabetic mouse model.

Type I diabetes (T1D) is a characterized by the inflammation of pancreatic islets and destruction of ß cells. Long and persistent uncontrolled diabetes tends to degenerate the immune system and increase the incidence of infections in diabetic individuals. Most serious diabetic complications are mediated by the free radicals, which damage multiple cellular components through direct effects of the cell cycle regulatory proteins. Camel whey protein (CWP) has antioxidant activity and decreases the effects of free radicals. However, the effects of CWP on lymphoid organs have not been studied in the context of diabetes. Therefore, the present study was designed to investigate the dietary influence of CWP supplementation on the lymphoid organs in streptozotocin (STZ)-induced type 1 diabetic mouse model. Three experimental groups were used: non diabetic control mice, diabetic mice, and diabetic mice treated with CWP. Induction of diabetes was associated with a marked reduction in glutathione (GSH) levels; decreased activities of GSH peroxidase (GSH Px), manganese superoxide dismutase (MnSOD) and catalase; increased reactive oxygen species (ROS) levels and iNOS activity in plasma and lymphoid organs. Furthermore, diabetic mice exhibited alterations in the expression of Bax and Bcl-XL, and subsequently pathological alterations in the architecture of the bone marrow, pancreas, thymus, and spleen. Interestingly, treatment of diabetic mice with CWP robustly restored glucose, insulin, GSH, and ROS levels and the activities of GSH Px, MnSOD, catalase and iNOS. Additionally, supplementation of diabetic mice with CWP improvement in the architecture of lymphoid tissues and rescued from apoptosis through direct effects on the Bax and Bcl-XL proteins. These data revealed the therapeutic potential of CWP against diabetic complications mediated damages of lymphoid organs.

Camel whey protein improves lymphocyte function and protects against diabetes in the offspring of diabetic mouse dams.

The prevalence of health problems in the offspring of pregnant diabetic mothers has recently been verified. Therefore, the present study was designed to investigate the influence of dietary camel whey protein (CWP), administered as a supplement to streptozotocin (STZ)-induced diabetic pregnant mice, on the efficiency of the immune system of the offspring. Three groups of female mice (n = 10) were used: non-diabetic control mice, diabetic mice, and diabetic mice orally administered CWP during the pregnancy and lactation periods. We then tested the immune response of B and T cells in adult male offspring (n = 15 in each group) by using flow cytometry, western blotting, and ELISAs. Our data demonstrated that the offspring of diabetic dams exhibited several postpartum complications, such as significant aberrant overexpression of activating transcription factor-3 (ATF-3), significant elevation of the plasma levels of pro-inflammatory cytokines (IL-1ß, IL-6, and TNF-α) and reactive oxygen species (ROS), marked decreases in the plasma levels of IL-2 and IL-7, significant inhibition of CCL21- and CXCL12-mediated chemotaxis of B- and T-lymphocytes, and a marked decrease in the proliferative capacity of antigen-stimulated B- and T-lymphocytes. Interestingly, administration of CWP to diabetic dams substantially restored the expression of ATF-3 and the levels of ROS, pro-inflammatory cytokines, IL-2, and IL-7 in the offspring. Furthermore, the chemotaxis of B- and T-lymphocytes toward CCL21 and CXCL12 and the proliferative capacities of these lymphocytes were restored in the male offspring of diabetic mice administered CWP. Our data provide evidence of a protective role of CWP in decreasing the tendency of the offspring of diabetic mothers to develop diabetes and related complications.

Oral supplementation of diabetic mice with propolis restores the proliferation capacity and chemotaxis of B and T lymphocytes towards CCL21 and CXCL12 by modulating the lipid profile, the pro-inflammatory cytokine levels and oxidative stress.

BACKGROUND: Type 1 diabetes mellitus (T1D) is a chronic autoimmune disease caused by the selective destruction of pancreatic ß cells, followed by hyperglycemia, oxidative stress and the subsequent extensive impairment of immune cell functions, a phenomenon responsible for the development of chronic diabetic complications. Propolis, a natural bee product that is extensively used in foods and beverages, significantly benefits human health. Specifically, propolis exerts antioxidant, anti-inflammatory and analgesic effects that may improve diabetic complications. To further elucidate the potential benefits of propolis, the present study investigated the effect of dietary supplementation with propolis on the plasma cytokine profiles, free radical levels, lipid profile and lymphocyte proliferation and chemotaxis in a streptozotocin (STZ)-induced type I diabetic mouse model. METHODS: Thirty male mice were equally distributed into 3 experimental groups: group 1, non-diabetic control mice; group 2, diabetic mice; and group 3, diabetic mice supplemented daily with an ethanol-soluble derivative of propolis (100 mg/kg body weight) for 1 month. RESULTS: First, the induction of diabetes in mice was associated with hyperglycemia and significant decreases in the insulin level and the lymphocyte count. In this context, diabetic mice exhibited severe diabetic complications, as demonstrated by a significant decrease in the levels of IL-2, IL-4 and IL-7, prolonged elevation of the levels of pro-inflammatory cytokines (IL-1ß, IL-6 and TNF-α) and reactive oxygen species (ROS) and altered lipid profiles compared with control non-diabetic mice. Moreover, antigen stimulation of B and T lymphocytes markedly reduced the proliferative capacity and chemotaxis of these cells towards CCL21 and CXCL12 in diabetic mice compared with control mice. Interestingly, compared with diabetes induction alone, treatment of diabetic mice with propolis significantly restored the plasma cytokine and ROS levels and the lipid profile to nearly normal levels. Most importantly, compared with untreated diabetic mice, diabetic mice treated with propolis exhibited significantly enhanced lymphocyte proliferation and chemotaxis towards CCL21 and CXCL12. CONCLUSION: Our findings reveal the potential immuno-modulatory effects of propolis, which acts as a natural antioxidant to enhance the function of immune cells during diabetes.

Effect of a high fat, high sucrose diet on the promotion of non-alcoholic fatty liver disease in male rats: the ameliorative role of three natural compounds.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a multifactorial disease with a complex pathophysiology. The clinical features of NAFLD include obesity, insulin resistance (IR) and dyslipidemia. Consumption of a diet high in saturated fats and sucrose is an important factor in the increasing occurrence of these metabolic disorders, primarily NAFLD and IR. We sought to assess the role of a high-fat, high-sucrose (HFS) diet in the promotion of NAFLD and to evaluate the effects of quercetin (Q), berberine (BB) and o-coumaric acid (CA) on modulation of these disorders. METHODS: Fifty male rats were divided into 2 main groups as follows: group 1 comprised 10 rats fed a standard diet (SD), and group 2 comprised 40 rats fed an HFS diet for 6 weeks and then subdivided equally into 4 groups; one of these groups served as the HFS diet and each of the other three groups received daily supplementation with either Q, CA or BB for 6 weeks. RESULTS: In the present study, several metabolic disorders were induced in our laboratory animal model, as evidenced by histological and biochemical changes. These alterations included serum and hepatic dyslipidemia (i.e., increased triglyceride, total cholesterol and low-density lipoprotein levels and decreased high-density lipoprotein levels), alterations in metabolic enzyme activities (lipase, glycerol-3-phosphate dehydrogenase, and glucose-6-phosphate dehydrogenase), histological changes in the liver (micro- and macrovesicular steatosis) and the downregulation of peroxisome proliferator-activated receptor γ (PPARγ) in adipose tissue and the liver. Daily oral supplementation with Q, CA or BB for 6 weeks after NAFLD induction had a hypolipidemic action and modulated metabolic markers. CONCLUSION: We showed that an HFS diet is able to promote NAFLD, and our results suggest that CA and BB are promising complementary supplements that can ameliorate the metabolic disorders associated with an HFS diet; however, Q requires further investigation.

Concentration-dependent antagonistic persuasion of SDS and naphthalene derivatives on the fibrillation of stem bromelain.

Sodium dodecyl sulfate, a biological membrane mimetic, can be used to study the conversion of globular proteins into amyloid fibrils in vitro. Using multiple approaches, the effect of SDS was examined on stem bromelain (SB), a widely recognized therapeutic protein. SB is known to exist as a partially folded intermediate at pH 2.0, situation also encountered in the gastrointestinal tract (its site of absorption). In the presence of sub-micellar SDS concentration (500-1000 µM), this intermediate was found to exhibit great propensity to form large-sized ß-sheeted aggregates with fibrillar morphology, the hall marks of amyloid structure. We also observed inhibition of fibrillation by two naphthalene-based compounds, ANS and bis-ANS. While bis-ANS significantly inhibited fibril formation at 50 µM, ANS did so at relatively higher concentration (400 µM). Alcohols, but not salts, were found to weaken the inhibitory action of these compounds suggesting the possible involvement of hydrophobic interactions in their binding to protein. Besides, isothermal titration calorimetry and molecular docking studies suggested that inhibition of fibrillation by these naphthalene derivatives is mediated not just through hydrophobic forces, but also by disruption of π-π interactions between the aromatic residues together with the inter-polypeptide chain repulsion among negatively charged ANS/bis-ANS bound SB.

Camel whey protein enhances diabetic wound healing in a streptozotocin-induced diabetic mouse model: the critical role of ß-Defensin-1, -2 and -3.

BACKGROUND: Delayed wound healing is considered one of the most serious diabetes-associated complications. The presence of replicating organisms such as bacteria within a diabetic's wound is considered one of the most important factors that impair cutaneous wound healing and the potential cellular and/or molecular mechanisms that are involved in the healing process. Defensins, which are anti-microbial peptides, have potent bactericidal activity against a wide spectrum of the bacterial and fungal organisms that are commonly responsible for wound infections. We recently demonstrated that camel whey proteins (WPs) expedite the healing of diabetic wounds by enhancing the immune response of wounded tissue cells and by alleviating some of the diabetic complications. METHODS: In the present study, we investigated the effects of WP supplementation on the mRNA and protein expression levels of ß-defensin-1 (BD-1), 2 and 3 and subsequently on the wound healing process in a streptozotocin (STZ)-induced diabetic mouse model. In this study, three groups of mice were used (10 mice per group): group 1, the non-diabetic mice (control); group 2, the diabetic mice; and group 3, the diabetic mice that received a daily supplement of undenatured WP (100 mg/kg of body weight) via oral gavage for 1 month. RESULTS: Compared with the non-diabetic control mice, the diabetic mice exhibited delayed wound closure that was characterized by a reduction in hydroxyproline content (indicator of collagen deposition), a marked elevation in free radical levels and a prolonged elevation in the levels of inflammatory cytokines, including interleukin-6 (IL-6), transforming growth factor-beta (TGF-ß) and tumor necrosis factor-alpha (TNF-α). Interestingly, compared with the diabetic mice that did not receive WP supplementation, the diabetic mice with WP had an accelerated closure and healing process of their wounds. The WP supplementation also decreased their levels of free radicals and restored their hydroxyproline content; proinflammatory cytokine levels; and expression of BD-1, 2 and 3 in the wounded tissue. CONCLUSION: WP supplementation may be beneficial for improving the healing and closure of diabetic wounds.

Treatment of diabetic mice with undenatured whey protein accelerates the wound healing process by enhancing the expression of MIP-1α, MIP-2, KC, CX3CL1 and TGF-ß in wounded tissue.

BACKGROUND: Continuous diabetes-associated complications are a major source of immune system exhaustion and an increased incidence of infection. Diabetes can cause poor circulation in the feet, increasing the likelihood of ulcers forming when the skin is damaged and slowing the healing of the ulcers. Whey proteins (WPs) enhance immunity during childhood and have a protective effect on some immune disorders. Therefore, in this study, we investigated the effects of camel WP on the healing and closure of diabetic wounds in a streptozotocin (STZ)-induced type I diabetic mouse model. RESULTS: Diabetic mice exhibited delayed wound closure characterized by a significant decrease in an anti-inflammatory cytokine (namely, IL-10) and a prolonged elevation of the levels of inflammatory cytokines (TNF-α, IL-1ß and IL-6) in wound tissue. Moreover, aberrant expression of chemokines that regulate wound healing (MIP-1α, MIP-2, KC and CX3CL1) and growth factors (TGF-ß) were observed in the wound tissue of diabetic mice compared with control nondiabetic mice. Interestingly, compared with untreated diabetic mice, supplementation with WP significantly accelerated the closure of diabetic wounds by limiting inflammatory stimuli via the restoration of normal IL-10, TNF-α, IL-1ß and IL-6 levels. Most importantly, the supplementation of diabetic mice with WP significantly modulated the expression of MIP-1α, MIP-2, KC, CX3CL1 and TGF-ß in wound tissue compared with untreated diabetic mice. CONCLUSION: Our data demonstrate the benefits of WP supplementation for improving the healing and closure of diabetic wounds and restoring the immune response in diabetic mice.

Supplementation with undenatured whey protein during diabetes mellitus improves the healing and closure of diabetic wounds through the rescue of functional long-lived wound macrophages.

Long and persistent uncontrolled diabetes tends to degenerate the immune system and increase the incidence of infections in diabetic patients. A serious complication of diabetes is impaired healing, which diminishes physical activity and, in some cases, leads to chronic wounds and limb amputation. Whey proteins (WPs) enhance immunity during early development and have a protective role in some immune disorders. The effect of camel WPs on wound healing in a streptozotocin-induced type 1 diabetic mice model was investigated. Sixty male mice were equally distributed into 3 experimental groups: group 1, non-diabetic control mice; group 2, diabetic mice; and group 3, diabetic mice that were orally supplemented with undenatured WP (100 mg/kg body weight/day for 1 month through oral gavage). We observed that the diabetic mice exhibited delayed wound closure characterized by a significant reduction in collagen deposition, prolonged elevation in inflammatory cytokines, aberrant activation of STAT3 and reduction in the activation of Akt and NF-κB when compared with the control mice. Moreover, in the diabetic mice, the wound-resident macrophages were dysfunctional and demonstrated increased apoptosis, a significant reduction in their phagocytotic ability, aberrant activation of STAT3 and a marked reduction in the activation of Akt. Interestingly, the supplementation of diabetic mice with WP significantly enhanced the collagen deposition, limited the inflammatory stimuli, restored the activation of STAT3, Akt and NF-κB and greatly improved the closure of diabetic wounds compared with the control mice. Most important, the supplementation of diabetic mice with WP rescued functional, long-lived wound-resident macrophages. Our data reveal the benefits of WP supplementation in improving the healing and closure of diabetic wounds.

Modulation of immune cell proliferation and chemotaxis towards CC chemokine ligand (CCL)-21 and CXC chemokine ligand (CXCL)-12 in undenatured whey protein-treated mice.

Whey protein concentrates (WPCs) enhance innate mucosal immunity during early life and have a protective role in some immune disorders. To further elucidate the potential benefits of this protein, the present study investigated the effect of dietary supplementation with WPCs on blood parameters, plasma cytokine profiles, and immune cell proliferation and chemotaxis. A total of 45 male mice were equally distributed into three experimental groups and treated daily for 21 days as follows: group I was a control group that was orally supplemented with distilled water, group II was orally supplemented with undenatured WP (100 mg/kg body weight), and group III was orally supplemented with bovine serum albumin (100 mg/kg body weight). We found that the plasma cytokine levels of interleukin (IL)-1α, IL-1ß, IL-10 and tumor necrosis factor-α and the levels of reactive oxygen species, cholesterol, triglycerides and the lipid profile were significantly decreased in the WP-treated group compared to the control group. In contrast, the levels of IL-2, IL-4, IL-7, IL-8 and glutathione were significantly elevated, and consequently, the ability of peripheral blood mononuclear cells to proliferate in response to stimulation with different antigens was significantly increased in the WP-treated group. Moreover, the in vitro chemotaxis of B, T and bone-marrow-derived dendritic cells toward CC chemokine ligand-21 and CXC chemokine ligand-12 was significantly increased, by twofold, in WP-treated mice compared to the control group. Taken together, our data reveal the benefits of WP supplementation in enhancing immune cell proliferation and migration to the secondary lymphoid organs.

Vitamin C supplementation reconstitutes polyfunctional T cells in streptozotocin-induced diabetic rats.

BACKGROUND: Studies have demonstrated that vitamin C supplementation enhances the immune system, prevents DNA damage, and decreases the risk of a wide range of diseases. Other study reported that leukocyte vitamin C level was low in diabetic individuals compared with nondiabetic controls. AIM OF THE WORK: To study the effect of vitamin C on oxidative stress, blood lipid profile, and T-cell responsiveness during streptozotocin (STZ)-induced type I diabetes mellitus. METHODS: Thirty male Sprague-Dawley rats were randomly split into three groups. The first served as a control group (n = 10) in which rats were injected with the vehicle alone. The second (n = 10) and the third groups (n = 10) were rendered diabetic by intraperitoneal (i.p.) injection of single doses of STZ (60 mg/kg body weight). The third group was supplemented with vitamin C (100 mg/kg body weight) for 2 months. RESULTS: T lymphocytes from the diabetic rats were found to be in a stunned state, with a decreased surface expression of the CD28 costimulatory molecule, low levels of phosphorylated AKT, altered actin polymerization, diminished proliferation and cytokine production, and, eventually, a marked decrease in abundance in the periphery. Vitamin C was found to significantly decrease the elevated levels of blood hydroperoxide, glucose, cholesterol, triglycerides and low-density lipoprotein (LDL) in diabetic rats. Furthermore, it was found to restore CD28 expression, AKT phosphorylation, actin polymerization, and polyfunctional T cells (IFN-γ- and IL-2-producing cells that exhibit a high proliferation capacity). CONCLUSION: Vitamin C treatment restores and reconstitutes polyfunctional, long-lived T cells in diabetic rats.

Thymoquinone decreases F-actin polymerization and the proliferation of human multiple myeloma cells by suppressing STAT3 phosphorylation and Bcl2/Bcl-XL expression.

BACKGROUND: Thymoquinone (TQ), the major active component of the medicinal herb Nigella sativa Linn., has been described as a chemopreventive and chemotherapeutic compound. METHODS: In this study, we investigated the effect of TQ on survival, actin cytoskeletal reorganization, proliferation and signal transduction in multiple myeloma (MM) cells. RESULTS: We found that TQ induces growth arrest in both MDN and XG2 cells in a dose- and time-dependent manner. TQ also inhibited CXC ligand-12 (CXCL-12)-mediated actin polymerization and cellular proliferation, as shown by flow cytometry. The signal transducer and activator of transcription (STAT) and B-cell lymphoma-2 (Bcl-2) signaling pathways may play important roles in the malignant transformation of a number of human malignancies. The constitutive activation of the STAT3 and Bcl-2 pathways is frequently observed in several cancer cell lines, including MM cells. Using flow cytometry, we found that TQ markedly decreased STAT3 phosphorylation and Bcl-2 and Bcl-XL expression without modulating STAT5 phosphorylation in MM cells. Using western blotting, we confirmed the inhibitory effect of TQ on STAT3 phosphorylation and Bcl-2 and Bcl-XL expression. CONCLUSIONS: Taken together, our data suggests that TQ could potentially be applied toward the treatment of MM and other malignancies.

Effects of undenatured whey protein supplementation on CXCL12- and CCL21-mediated B and T cell chemotaxis in diabetic mice.

BACKGROUND: Long and persistent uncontrolled diabetes tends to degenerate the immune system and leads to an increased incidence of infection. Whey proteins (WPs) enhance immunity during early life and have a protective role in some immune disorders. In this study, the effects of camel WP on the chemotaxis of B and T cells to CXCL12 and CCL21 in diabetic mice were investigated. RESULTS: Flow cytometric analysis of the surface expressions of CXCR4 (CXCL12 receptor) and CCR7 (CCL21 receptor) on B and T cells revealed that the surface expressions of CXCR4 and CCR7 were not significantly altered in diabetic and WP-supplemented diabetic mice compared with control mice. Nevertheless, B and T lymphocytes from diabetic mice were found to be in a stunned state, with a marked and significant (P < 0.05) decrease in CXCL12- and CCL21-mediated actin polymerization and subsequently, a marked decrease in their chemotaxis. WP supplementation in the diabetes model was found to significantly increase CXCL12- and CCL21-mediated actin polymerization and chemotaxis in both B and T cells. CONCLUSION: Our data revealed the benefits of WP supplementation in enhancing cytoskeletal rearrangement and chemotaxis in B and T cells, and subsequently improving the immune response in diabetic mice.

Thymoquinone inhibits the CXCL12-induced chemotaxis of multiple myeloma cells and increases their susceptibility to Fas-mediated apoptosis.

In multiple myeloma (MM), malignant plasma cells reside in the bone marrow, where they accumulate in close contact with stromal cells. The mechanisms responsible for the chemotaxis of malignant plasma cells are still poorly understood. Thus, we investigated the mechanisms involved in the chemotaxis of MDN and XG2 MM cell lines. Both cell lines strongly expressed CCR9, CXCR3 and CXCR4 chemokine receptors but only migrated toward CXCL12. Activation of CXCR4 by CXCL12 resulted in the association of CXCR4 with CD45 and activation of PLCß3, AKT, RhoA, IκBα and ERK1/2. Using siRNA-silencing techniques, we showed CD45/CXCR4 association is essential for CXCL12-induced migration of MM cells. Thymoquinone (TQ), the major active component of the medicinal herb Nigella sativa Linn, has been described as a chemopreventive and chemotherapeutic compound. TQ treatment strongly inhibited CXCL12-mediated chemotaxis in MM cell lines as well as primary cells isolated from MM patients, but not normal PBMCs. Moreover, TQ significantly down-regulated CXCR4 expression and CXCL12-mediated CXCR4/CD45 association in MM cells. Finally, TQ also induced the relocalization of cytoplasmic Fas/CD95 to the membrane of MM cells and increased CD95-mediated apoptosis by 80%. In conclusion, we demonstrate the potent anti-myeloma activity of TQ, providing a rationale for further clinical evaluation.