Ankur Datta

Antidiabetic and antihyperlipidemic activity of hydroalcoholic extract of Withania coagulans Dunal dried fruit in experimental rat models

Objective: Evaluation of antidiabetic potential of the hydroalcoholic extract of Withania coagulans Dunal dried fruit (WCDF) alone and in combination with glipizide, in streptozotocin-induced diabetes, and evaluation of possible antihyperlipidemic activity of the same extract in high-cholesterol diet-induced hyperlipidemia, in albino rats. Materials and Methods: Experimental diabetes was induced in 30 albino rats with intraperitoneal injection of streptozotocin (55 mg/kg). The rats were divided into five groups receiving the following treatments orally for 4 weeks: Vehicle, glipizide (2.5 mg/kg), WCDF extract (1000 mg/kg), WCDF extract (1000 mg/kg) plus glipizide (1 mg/kg) and WCDF extract (1000 mg/kg) plus glipizide (2.5 mg/kg). Fasting and postprandial blood glucose levels were measured every week for 4 weeks. Endocrine pancreas histopathology was done at the end. In a separate set of experiment, five groups of six albino rats each, received orally for 4 weeks, vehicle, cholesterol (25 mg/kg/day), cholesterol (25 mg/kg/day) plus atorvastatin (7.2 mg/kg/day), cholesterol (25 mg/kg/day) plus WCDF extract (1000 mg/kg/day) and no treatment, respectively. Estimation of serum lipid profile and liver histopathology was done at the end of 4 weeks. Statistical Analysis: Between-group and within-group comparisons were respectively done by analysis of variance (ANOVA) and repeated measures ANOVA, followed by post hoc Tukeys test, with a significance level of P < 0.05. Results and Conclusions: The 4-week treatment with WCDF extract significantly reversed hyperglycemia in streptozotocin-induced diabetes that was comparable to glipizide. When combined with glipizide (2.5 mg/kg), WCDF extract produced a synergistic antihyperglycemic effect as well as improvement in pancreatic histopathology. Moreover, hydroalcoholic extract of WCDF was effective and comparable to atorvastatin in controlling the high-cholesterol diet-induced hyperlipidemia in rats.

Overview of Current and Upcoming Strategies Implied for the Therapy of Type 2 Diabetes Mellitus

Population explosion, urbanization, changes in lifestyle management, improper food habits and various other factors play focal contributors in the massive prevalence of type 2 diabetes mellitus in the developing countries. Although insulin is the cornerstone in the management of type 1 diabetes; insulin, anti-hyperglycemic and hypoglycemic agents are proved to be effective in type 2 diabetes, although their efficacy decreases with the progress of the disease. Moreover a significant number of side effects, mostly hypoglycemia and weight gain have put a bar in using these drugs confidently. Many novel therapeutic strategies with convincing efficacy and less adverse effects are currently emerging for providing efficient means of treatment of this disorder. This article mainly focuses on newer and unconventional pharmaceutical or biotechnical strategies that may or may not have been implied for the treatment of Type 2 Diabetes mellitus on a widescale basis so far. These strategies are supposed to be efficient in controlling glycemic levels and possess a significant potential to reduce the co-morbidities associated with this disease.

A Comparative Study of Lipid-Lowering Effects of Guggul and Atorvastatin Monotherapy in Comparison to Their Combination in High Cholesterol Diet-Induced Hyperlipidemia in Rabbits

ABSTRACT Background: Hypolipidemic activity of gugulipid has been widely described in traditional literature. Objective: This study was done to evaluate hypolipidemic activity of guggul and atorvaststin monotherapy in comparison to their combination in rabbits. Materials and Methods: Male New Zealand White rabbits (body weight 1.3–1.8 kg and age 8–10 weeks) were made hyperlipidemic by feeding cholesterol (0.5 g/kg) for three weeks and randomly divided into a control and three treatment groups receiving: atorvastatin (3.7 mg/kg), guggul (3.5 mg/kg) and their combination (same dose) for the next three weeks. Body weight measurements, estimation of serum lipid profile were done at the beginning, after three and six weeks, respectively. Histopathological examination of liver, heart and aorta was done after six weeks. Statistical analysis was done with SPSS version 16.0 using one-way and repeated measures analysis of variance (ANOVA) followed by post-hoc multiple comparison test with two tailed P value < 0.05 as significant. Results: All treated groups had significant reduction in cholesterol, triglyceride, low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL) in comparison to pre-treatment values and control group, and had significant increase in high-density lipoprotein (HDL) in comparison to pre-treatment values. Conclusion: Combination of atorvastatin and guggul was comparable to their monotherapies in improving lipid profile.

Specific allergen immunotherapy attenuates allergic airway inflammation in a rat model of Alstonia scholaris pollen induced airway allergy

Pollen grains are well established to be an important cause of respiratory allergy. Current pharmacologic therapies for allergic asthma do not cure the disease. Allergen specific immunotherapy is the only treatment method which re-directs the immune system away from allergic response leading to a long lasting effect. The mechanism by which immunotherapy achieves this goal is an area of active research world-wide. The present experimental study was designed to develop an experimental model of allergic lung inflammation based on a relevant human allergen, Alstonia scholaris pollen, and to establish the immunological and cellular features of specific allergen immunotherapy using this same pollen extract. Our results revealed that Alstonia scholaris pollen sensitization and challenge causes eosinophilic airway inflammation with mucin hypersecretion. This is associated with increased total IgE, increased expression of FcɛRI on lung mast cells and increased levels of IL-4, IL-5 & IL-13 as confirmed by ELISA, in-situ immunofluorescence and FACS assay. Allergen specific immunotherapy reduced airway inflammation and also decreased total IgE level, FcɛRI expression, IL-4, IL-5 & IL-13 levels. It was further noted that the reduction of these levels was more by intra-nasal route than by intra-peritoneal route. Thus we present a novel animal model of Alstonia scholaris pollen allergic disease and specific allergen immunotherapy which will pave the way towards the development of better treatment modalities.

T11TS Treatment Augments Apoptosis of Glioma Associated Brain Endothelial Cells, Hint towards Anti‐Angiogenic Action in Glioma

Malignant glioma continues to be a clinical challenge with an urgent need for developing curative therapeutic intervention. Apoptosis induction in tumor‐associated endothelial cells represent a central mechanism that counteracts angiogenesis in glioma and other solid tumors. We previously demonstrated that intraperitoneal administration of sheep erythrocyte membrane glycopeptide T11‐target structure (T11TS) in rodent glioma model inhibits PI3K/Akt pathway and Raf/MEK/ERK signaling in glioma‐associated brain endothelial cells. In the present study, we investigated whether T11TS treatment influence apoptosis signaling in vivo in glioma‐associated brain endothelial cells. Annexin‐V/PI staining showed that T11TS treatment in glioma‐induced rats increases apoptosis of glioma‐associated endothelial cells within glioma milieu compared to brain endothelial cells in glioma induced and control groups. Flowcytometric JC‐1 assay revealed that T11TS administration triggers loss of mitochondrial membrane potential in glioma‐associated brain endothelial cells. Flowcytometry, immunoblotting, and in situ immunofluoresecnt imaging were employed to investigate the effect of T11TS on apoptotic regulatory proteins in brain endothelial cells. T11TS treatment‐upmodulated expression of p53, Bax, Fas, FasL, and FADD in glioma associated endothelial cells and downregulated Bcl‐2 protein. T11TS therapy induced cytochrome‐c release into cytosol, activated caspase −9, 8, 3, and cleaved Bid in glioma associated brain endothelial cells. The study demonstrates that T11TS induces apoptosis in glioma‐associated brain endothelial cells via p53 accumulation and activation of intrinsic as well as Fas‐dependent extrinsic pathway. The pro‐apoptotic action of T11TS on glioma‐associated endothelial cells provides crucial insight into how T11TS exerts its anti‐angiogenic function in glioma. J. Cell. Physiol. 232: 526–539, 2017.

Modulation of regulatory T cells by intranasal allergen immunotherapy in an experimental rat model of airway allergy

Abstract Allergic airway diseases such as asthma and allergic rhinitis are increasing in prevalence worldwide. The theory of an altered Th1/Th2 balance in allergic diathesis has recently been termed a “procrustean paradigm” as it failed to explain many preclinical findings. Regulatory T cells (Treg) have now been shown to be critical in T‐cell homeostasis and in the maintenance of peripheral tolerance to allergens. Allergen specific immunotherapy (SIT) has been shown to induce regulatory T cells in allergic patients. Among various types of SIT, intranasal immunotherapy had not been studied in detail for the treatment of allergic airway diseases. So, there was a need to study the contribution of regulatory T cells and their mechanistic pathways following intranasal immunotherapy in‐vivo. It had been previously shown that intranasal allergen immunotherapy using Alstonia scholaris pollen extract abrogates allergic airway inflammation with decline in IgE and Th2 cytokine levels. The present study for the first time offers a multi‐targeted approach towards attenuation of airway allergy by the generation of CD4 + CD25 + Foxp3 + T cells and other subsets of Treg cells like Tr1 cells, Th3 cells, CTLA4 + Treg cells, and also modulation of various Treg cell surface molecules like GITR, OX40, CD39 and CD73 by intranasal immunotherapy in the same animal model. This animal experiment will thus help to chart out newer molecular targets for treating allergic asthma or rhinitis. Graphical abstract Figure. No caption available. HighlightsIntranasal allergen Immunotherapy effectively induces immune tolerance in Alstonia scholaris pollen allergy.Foxp3 expression in Treg cells is decreased in airway allergy, which is increased after intranasal allergen immunotherapy.Intranasal allergen immunotherapy upregulates GITR, CTLA 4, TGF&bgr;, CD39, CD73, IL10 and downregulates OX40 on Treg cells.

Allergen immunotherapy modulates sensitivity of Treg cells to apoptosis in a rat model of allergic asthma

AIM To study the apoptosis of Foxp3+ Treg cells following Alstonia scholaris pollen sensitization-challenge and following allergen immunotherapy. MATERIALS & METHODS Wistar rats were sensitized-challenged with Alstonia scholaris pollen and were further given intranasal immunotherapy. For the analysis of the apoptotic proteins on Treg cells by flow cytometry, multiple gating procedures were followed. RESULTS Allergen sensitization-challenge increases Annexin-V, Fas, FasL, caspases-8, 9, 3 cytochrome-C, APAF-1, Bax, perforin-1 and granzyme-B on Treg cells which is decreased following intranasal immunotherapy. On the other hand, Bcl-2 expression is decreased in allergy and increased by immunotherapy. CONCLUSION Apoptosis of Treg cells is increased following allergen sensitization-challenge via extrinsic, intrinsic and perforin/granzyme pathways and allergen immunotherapy decreased the sensitivity to apoptosis of Treg cells.

Hepatotoxicity of atenolol therapy - A report of 2 cases

Abstract This case report highlights atenolol induced episodes of chronic and acute hepatotoxicities in 2 elderly hypertensive patients. The 1st patient manifested liver dysfunction after 8 months of 50 mg daily atenolol therapy and in the 2nd patient liver dysfunction was revealed within 3 weeks of 100 mg daily atenolol intake. There was no evidence of any other possible hereditary, traumatic, surgical, metabolic, infective, organic, or pathologic causes giving rise to these conditions. Possibilities of drug interactions were carefully ruled out and these episodes of hepatotoxicities were ‘probably’ drug (atenolol) induced, as depicted by CIOMS/RUCAM scale. Withdrawal of the offending drug resulted in reversal of the diseased states. Routine liver function tests may be warranted in patients on atenolol therapy.

T11TS IMMUNOTHERAPY REPAIRS PI3K-AKT SIGNALING IN T-CELLS: CLUES TOWARDS ENHANCED T-CELL SURVIVAL IN RAT GLIOMA MODEL†

Malignant glioma is the most fatal of astrocytic lineage tumors despite therapeutic advances. Onset and progression of gliomas is accompanied by severe debilitation of T‐cell defense and T‐cell survival. One of the chief contributors to T‐cell survival downstream of activation is the PI3K‐AKT pathway. Our prior studies showed that the novel immunotherapeutic molecule T11‐target structure (T11TS) blocks T‐cell apoptosis in glioma. We also showed activation of immunological synapse components and calcineurin‐NFAT pathway following T11TS immunotherapy of glioma‐bearing rats. This lead to investigations whether such T‐cell activation upon T11TS therapy translates into activation of downstream PI3K/AKT signals which may be related to observed blockade of T‐cell apoptosis. For the purpose, we assessed by flowcytometry and immunoblotting, expressions of PI3K, PDK1, AKT, p‐AKT, and PTEN in splenic T‐cells of normal, experimentally‐induced glioma‐bearing rats and glioma‐bearing rats receiving first, second and third doses of T11TS. We also determined comparative nuclear translocation of NF‐κB across groups. We found significant increases in T‐cell expressions of PDK1, PI3K, and p‐AKT in T11TS‐treated animal groups compared to sharp downregulations in glioma. AKT levels remained unchanged across groups. PTEN levels declined sharply after T11TS immunotherapy. T11TS also caused enhanced NF‐κB translocation to the T‐cell nucleus compared to glioma group. Results showed heightened activation of the PI3K‐AKT pathway in glioma‐bearing rats following T11TS immunotherapy. These results illustrate the novel role of T11TS immunotherapy in ameliorating the PI3K pathway in T‐cells in glioma‐bearing animals to enhance T‐cell survival, according greater defense against glioma. The study thus has far‐reaching clinical outcomes.

T11TS repress gliomagenic apoptosis of bone marrow hematopoietic stem cells

Combating gliomagenic global immunosuppression is one of the emerging key for improving prognosis in malignant glioma. Apoptosis plays a pivotal role within the adult hematopoietic system particularly in regulating the cells of immune system. Gliomagenic regulation of apoptotic mediators within bone marrow milieu has not been elucidated. We previously demonstrated that administration of membrane glycopeptides T11 target structure (T11TS) not only rejuvenate bone marrow hematopoietic stem cells (BMHSCs) from glioma mediated hibernation by inhibiting gliomagenic overexpression of Ang‐1/Tie‐2 but also stimulate glioma mediated diminution of expression CD34, c‐kit, and Sca‐1 markers. In the present study, we investigated the impact of glioma on apoptotic signaling cascades of BMHSCs and consequences following T11TS therapy. Bone marrow smear and Annexin V staining confirm gliomagenic acceleration of apoptotic fate of BMHSCs whereas T11TS treatment in glioma‐bearing rats disrupted apoptosis of BMHSCs. Flowcytometry, immunoblotting, and immunofluorescence imagining results revealed multi potent T11TS not only significantly downregulates gliomagenic overexpression of Fas, Fas L, Bid, and caspase‐8, the pro‐apoptotic extrinsic mediators but also strongly inhibits cytosolic release of cytochrome‐c, Apf‐1, and Bax to deactivate gliomagenic caspase‐9, 3 the key intrinsic apoptotic mediators followed by up modulation of anti‐apoptotic Bcl‐2 in glioma associated HSCs. T11TS is also able to diminish the perforin‐granzyme B mediated apoptotic verdict of BMHSCs during gliomagenesis. The anti‐apoptotic action of T11TS on glioma associated BMHSCs provide a crucial insight into how T11TS exerts its immunomodulatory action against glioma mediated immune devastation.