Kamlesh Kumar Pant

Melatonin protects against experimental reflux esophagitis

Abstract:  Reflux esophagitis (RE), a major gastrointestinal disorder results from excess exposure of the esophageal mucosa to acidic gastric juice or bile‐containing duodenal contents refluxed via an incompetent lower esophageal sphincter. Recent studies implicated oxygen derived free radicals in RE induced esophageal mucosal damage resulting in mucosal inflammation. Thus, control over free radical generation and modulation of inflammatory responses might offer better therapeutic effects to counteract the severity of RE. In this context we investigated the effect of melatonin against experimental RE in rats. Melatonin pretreatment significantly reduced the haemorrhagic lesions and decreased esophageal lipid peroxidation aggravated by RE. Moreover, the depleted levels of superoxide dismutase and glutathione observed in RE were replenished by melatonin signifying its free radical scavenging properties and antioxidant effects resulting in the improvement of esophageal defense mechanism. Further melatonin repressed the upregulated levels of expression of proinflammatory cytokines like, TNF‐α, IL‐1β and IL‐6 in RE. However, increased levels of the anti‐inflammatory cytokine IL‐10 remained unaltered after melatonin administration signifying its immunomodulatory effect through suppression of Th1‐mediated immune responses. The involvement of receptor dependent actions of melatonin against RE were also investigated with MT2 receptor antagonist, luzindole (LUZ). LUZ failed to antagonize melatonin’s protective effects against RE indicating that melatonin mediated these beneficial effects in a receptor‐independent fashion. Thus, esophageal mucosal protection elicited by melatonin against experimental RE is not only dependent on its free radical scavenging activity but also mediated in part through its effect on the associated inflammatory events in a receptor‐independent manner.

Role of neuroinflammation and latent transcription factors in pathogenesis of Parkinson’s disease

Parkinson’s disease (PD) the second most common age-associated progressive neurodegenerative disorder is characterized by loss of dopaminergic neurons, cytoplasmic inclusions of aggregated proteins (Lewy bodies), and neuroinflammation. The inflammation of neurons causes release of various inflammatory mediators (IFNs, EGF, IL5, IL6, HGF, LIF and BMP2). The hallmarks of neuroinflammation are the presence of activated microglia and reactive astrocytes in the parenchyma of the CNS and increased production of cytokines, chemokines, prostaglandins, complement cascade proteins, and reactive oxygen and nitrogen species (ROS/RNS) which in some cases can result in disruption of the blood brain barrier and direct participation of the adaptive immune system. Latent transcription factors such as NF-κB, STAT 3, AP1, and SMAD 7, Toll like receptors and FAF 1 are constitutively upregulated in activated microglia. Toll-like receptors when activated promote NF-κB signaling thus promoting a vicious cycle of neuroinflammation. These transcription factors take dopaminergic neurons to apoptotic pathway via p53 and other death domain receptors. Neuroprotective signaling pathways such as mTOR, SOCS, and TGF-β down regulated during development of PD. YY1 signaling, which has protective effect against α-Synuclein toxicity, is significantly decreased in PD patients. In summary we can say that transcription factors promoting inflammation such as NF-κB, STAT 3, AP 1, and Toll-like receptors are constitutively upregulated in PD, while neuroprotective pathways such as mTOR, TGF-β, and YY1 are substantially downregulated in microglia of PD patients.

Tobacco Exposure by Various Modes May Alter Proinflammatory (IL-12) and Anti-Inflammatory (IL-10) Levels and Affects the Survival of Prostate Carcinoma Patients: An Explorative Study in North Indian Population

Objective. Inflammation is an important hallmark of all cancers and net inflammatory response is determined by a delicate balance between pro- and anti-inflammatory cytokines, which may be affected by tobacco exposure, so the present study was designed to explore the effect of various modes of tobacco exposure on interleukin-12 (IL-12) and interleukin-10 (IL-10) inflammatory cytokine levels and survival in prostate carcinoma (PCa) patients. Methods. 285 cancer patients and equal controls with 94 BPH (benign prostatic hyperplasia) were recruited; baseline levels of serum IL-12 and IL-10 were measured and analyzed in various tobacco exposed groups by appropriate statistical tool. Five-year survivals of patients were analyzed by Log-rank (Mantel-Cox) test (graph pad version 5). Results. The expression of serum proinflammatory (IL-12) and anti-inflammatory (IL-10) cytokines was correlated with tobacco exposed group as smokers, chewers, and alcohol users have shown significantly higher levels (P < 0.001) with significantly lower median survivals (27.1 months, standard error = 2.86, and 95% CI: 21.4–32.62); than nonusers. Stages III and IV of tobacco addicted patients have also shown significantly increased levels of IL-12 and IL-10. Conclusions. IL-12 and IL-10 seem to be affected by various modes of tobacco exposure and inflammation also affects median survival of cancer patients.

Design of potential siRNA molecules for hepatitis delta virus gene silencing.

Hepatitis D is a liable reason of mortality and morbidity worldwide. It is caused by an RNA virus known as Hepatitis Delta Virus (HDV). Genetic studies of HDV have shown that delta antigen protein is responsible for replication of genome and play a foremost role in viral infection. Therefore, delta antigen protein may be used as suitable target for disease diagnosis. Viral activity can be restrained through RNA interference (RNAi) technology, an influential method for post transcriptional gene silencing in a sequence specific manner. However, there is a genetic variability in different viral isolates; it is a great challenge to design potential siRNA molecules which can silence the respective target genes rather than any other viral gene simultaneously. In current study two effective siRNA molecules for silencing of HDV were rationally designed and validated using computational methods, which may lead to knockdown the activity of virus. Thus, this approach may provide an insight for the chemical synthesis of antiviral RNA molecule for the treatment of hepatitis D, at genome level.

Genetic variability at promoters of IL-18 (pro-) and IL-10 (anti-) inflammatory gene affects susceptibility and their circulating serum levels: An explorative study of prostate cancer patients in North Indian populations.

Inflammation is an important hallmark of all types of cancers with a well-established role in carcinogenesis. The net inflammatory response is determined by the balance between pro- and anti-inflammatory cytokines, the levels of which may be affected by the genetic make-up. Interleukin (IL)-18, a pro-inflammatory cytokine expressed by various cells including those of the prostate, is a key mediator of anti-cancer immune response. IL-10, an anti-inflammatory cytokine associated with tumour malignancy, causes escape from immune surveillance. This study hypothesizes that genetic variants of IL-18 (-607 C/A and -137 G/T) and IL-10 (-819 C/T and -592 C/A) may influence the circulating levels of these interleukins, thereby generating susceptibility risk to prostate cancer. The study was conducted on 676 subjects (controls and patients of prostate cancer (PCa): 291 each; and 94 patients with benign prostate hypertrophy (BPH)). Genotyping was performed by PCR-RFLP and Real-Time PCR probe-based method. Circulating interleukin levels were obtained by ELISA. Circulating IL-18 levels were significantly elevated in cancer and BPH patients carrying GG genotypes for -137 of IL-18. The trend of circulating IL-18 levels was GG>GC>CC, observed in all groups. The -137 genetic variants of IL-18 significantly associated with PCa risk were GC, CC, and GC+CC, compared to GG (OR: 1.71, 95% CI: 1.20-2.46; OR: 3.35, 95% CI: 2.03-5.53; and OR: 2.05, 95% CI: 1.46-2.87, respectively). A significant association of AA and CA+AA against CC genotype was observed at -607 locus of IL-18 (OR: 0.46, 95%CI: 0.29-0.72; OR: 0.61, 95% CI: 0.41-0.90, respectively). Significantly elevated levels of IL-10 were observed with TT (wild) genotype at -819 of IL-10, compared to the CC (homozygous mutant) genotype in all three groups of subjects. However, no significant association was found between IL-10 promoter genotypes and PCa risk. We conclude that genetic variants of IL-18 and IL-10 promoters influence the circulating levels of these interleukins. Variations at -137 and -607 loci of IL-18 are associated with susceptibility to PCa.

Tobacco exposure may enhance inflammation in prostate carcinoma patients: An explorative study in north Indian population

Prostate cancer is responsible for major deaths globally after lung cancer. However, etiology of prostate cancer is still unknown. Individual risk and incidence of prostate cancer may result from the interaction of genetic susceptibility with exposure to environmental factors such as infectious agents, tobacco, occupational exposure, dietary carcinogens, and/or hormonal imbalances leading to injury of the prostate and to the development of chronic inflammation. About 30% of all human cancers are caused by tobacco smoking and inhaled pollutants. Inflammation is now regarded as an important hallmark of cancer. The present study has been aimed to explore the pro-inflammatory levels in prostate carcinoma patients by examining the serum levels of novel cytokine interleukin-18 (IL-18) expression in tobacco exposed population. A total of 578 (n = 284 biopsy proven prostate cancer patients, n = 294 controls with and without tobacco exposed population) were recruited. Serum IL-18 (Interleukin-18) level was done by ELISA. The IL-18 levels between cancer patients and controls within same mode tobacco exposure as tobacco smoking (overall) showed significant difference (P < 0.0001) and further we compared within stratified group, it significantly differ (P < 0.0001) in bidi and cigarette smoking than control non users. Furthermore, IL-18 levels in tobacco chewers (overall) with gutkha and khaini chewers showed significant difference (P < 0.01) than controls non users. Moreover, the IL-18 levels between cancer patients and controls with in of combined mode chewers smokers and alcohol (CSA), smokers with alcohol showed significant difference (P < 0.01) than controls. The IL-18 levels also differed significantly (P < 0.05) with smokers and chewers in higher stages of III and IV, and showed non significant with in lower stages. Tobacco exposure enhance the inflammation in prostate carcinoma patients in stratified group as it have been represented as a risk factors in various cancers, but this study provide further its role that seems to influence inflammation especially in prostate carcinoma.

Protective role of theophylline and their interaction with nitric oxide (NO) in adjuvant-induced rheumatoid arthritis in rats.

Theophylline (non-specific PDE inhibitor) and their interactions with nitric oxide modulators were evaluated in adjuvant-induced arthritic model of rats. Wistar rats (200-300g), 8 animals per group were used in the study. The animals were injected with 0.1mL of squalene and 0.2mL of complete Freunds adjuvant on day (0) in sub-planter region of right hind paw controls received only saline. The treatment with theophylline and nitric oxide modulators were done from day 14 to day 28. Arthritis indexes, ankle diameter, paw volume, and body weight were determined to assess RA progression from day (0) to day 28. On day 28 animals were sacrificed and their blood collected for IL-10 and TNF-α cytokine levels and hind paw for pathological analysis. Synovial fluid from joint spaces of CFA inoculated rats was collected to estimate TNF-α level in synovial fluid. The data obtained was analyzed by two-way ANOVA followed by the Newman-Keuls post-hoc test. Theophylline (10 and 20mg/kg) significantly decreased adjuvant induced increased arthritis-index, paw volume and ankle diameter (p<0.05 in all parameters) compared to only adjuvant control group. It also reversed adjuvant induced slight decrease in body weight to normalcy. l-Arginine 100mg/kg+theophylline 20mg/kg suppressed TNF-α and elevates IL-10 level as well as reversed adjuvant-induced elevated arthritic parameters as compared to only adjuvant and prednisone group (p<0.001). Synovial TNF-α level of adjuvant only group was several fold higher than its serum level. Treatment with theophylline 20mg/kg significantly reduces synovial TNF-α level as compared to adjuvant only group. Theophylline 20mg/kg+L-NAME 10mg/kg significantly reversed these adjuvant-induced changes in immunological, histopathological and arthritis parameters (p<0.05).

Efficacy of crude extract of Emblica officinalis (amla) in arsenic-induced oxidative damage and apoptosis in splenocytes of mice

Introduction: Arsenic, an environmental contaminant naturally occurred in groundwater and has been found to be associated with immune-related health problems in humans. Objective: In view of increasing risk of arsenic exposure due to occupational and non-occupational settings, the present study has been focused to investigate the protective efficacy of amla against arsenic-induced spleenomegaly in mice. Results: Arsenic exposures (3 mg/kg body weight p.o for 30 days) in mice caused an increase production of ROS (76%), lipid peroxidation (84%) and decrease in the levels of superoxide dismutase (53%) and catalase (54%) in spleen as compared to controls. Arsenic exposure to mice also caused a significant increase in caspases-3 activity (2.8 fold) and decreases cell viability (44%), mitochondrial membrane potential (47%) linked with apoptosis assessed by the cell cycle analysis (subG1-28.72%) and annexin V/PI binding in spleen as compared to controls. Simultaneous treatment of arsenic and amla (500 mg/kg body weight p.o for 30 days) in mice decreased the levels of lipid peroxidation (33%), ROS production (24%), activity of caspase-3 (1.4 fold), apoptosis (subG 1 12.72%) and increased cell viability (63%), levels superoxide dismutase (80%), catalase (77%) and mitochondrial membrane potential (66%) as compared to mice treated with arsenic alone. Conclusions: Results of the present study indicate that the effect of arsenic is mainly due to the depletion of glutathione in liver associated with enhanced oxidative stress that has been found to be protected following simultaneous treatment of arsenic and amla.

Significance of impaired serum gelatinases activities in metabolic syndrome

Introduction: A consortium of metabolic risk factors accelerate the onset of diabetes, heart disease, stroke, and certain cancers. Proteolytic enzymes like matrix metalloproteinases (MMP) are regulated by a group of endogenous proteins called tissue inhibitors of metalloproteinases (TIMP). These TIMPs binds to active and alternate sites of activated MMPs and facilitate regulation. Impaired expression of MMPs may have a significant contribution in the pathogenesis of many tissues-destructive processes like tumor progression and cardiovascular and metabolic disorders. Materials and Methods: This case control study lays stress on the possible role of impaired levels of circulating MMP-2 and 9 in metabolic syndrome (MetS). The age, sex-matched 388 subjects with 190 newly diagnosed patients, and 198 healthy controls were recruited. To screen the patients with MetS, biochemical analysis of patients for impaired glucose level, hypertension, body mass index (BMI), and lipid profile was performed. The circulating level of MMP-2 and -9 in serum was analyzed by enzyme-linked immunosorbent assay (ELISA) in all patients and control. Results: All metabolic risk factors were statistically significant (P < 0.01) in patients against control group. The serum MMP-2 and -9 level was significantly higher (P < 0.001) in patients having MetS as compared with control group. Conclusions: Similar trend was observed in gender wise analysis of serum MMP level. Higher MMP level alteration observed in male patients as compared with female patients.

Functional genetic variability at promoters of pro-(IL-18) and anti-(IL-10) inflammatory affects their mRNA expression and survival in prostate carcinoma patients: Five year follow-up study.

Inflammation is an important hallmark of all cancers. The net inflammatory response is determined by a delicate balance between pro‐ and anti‐inflammatory cytokines, which, in turn, is determined by the genetic make‐up. The present study investigates the role of variations in the promoter regions of IL‐18 and IL‐10 (anti‐inflammatory) cytokines on mRNA expressions and survival in prostate cancer (PCa) patients.