Moderate Rainfall and High Humidity During the Monsoon Season, Negligence in Using Malaria Protection Methods and High Proportion of Mild Symptomatic Patients Were the Driving Forces for Upsurge of Malaria Cases in 2018 Among Tea Tribe Populations in Endemic Dolonibasti Health Sub-center, Udalguri District, Assam State, North-East India.

Malaria elimination is a global priority, which India has also adopted as a target. Despite the malaria control efforts like long-lasting insecticidal nets distribution, rounds of indoor residual spray, the introduction of bi-valent rapid diagnostic tests and artemisinin combination therapy, malaria remained consistent in Dolonibasti sub-center of Orang block primary health center (BPHC) under the district Udalguri, Assam state followed by abrupt rise in cases in 2018. Therefore, we aimed to investigate the factors driving the malaria transmission in the outbreak area of Dolonibasti sub-center. Malaria epidemiological data (2008-2018) of Udalguri district and Orang BPHC was collected. The annual (2011-2018) and monthly (2013-2018) malaria and meteorological data of Dolonibasti sub-center was collected. An entomological survey, Knowledge, Attitude and Practices study among malaria cases (n = 120) from Dolonibasti was conducted. In 2018, 26.1 % (2136/ 8188) of the population of Dolonibasti were found to be malaria positive, of which 55% were adults (n = 1176). Majority of cases were from tea tribe populations (90%), either asymptomatic or with fever only, 67.5 % (81/120) had experienced malaria infection during past years. The outbreak was characterized by a strong increase in cases in June 2018, high proportion of slide falciparum rate of 26.1% (other years average, 15.8%) and high proportion of P. falciparum of 81.2 % (other years average, 84.3%). Anopheles minimus s.l. was the major vector with 28.6% positivity and high larval density in paddy fields/ drainage area. Annual relative humidity was associated with rise in malaria cases, annual parasite incidence (rs = 0.69, 90%CI; p = 0.06) and slide positivity rate (rs = 0.83, 95%CI; p = 0.01). Older people were less educated (rs = -0.66; p < 0.001), had lesser knowledge about malaria cause (rs = -0.42; χ2=21.80; p < 0.001) and prevention (rs = -0.18; p = 0.04). Malaria control practices were followed by those having knowledge about cause of malaria (rs = 0.36; χ2 = 13.50; p < 0.001) and prevention (rs = 0.40; χ2 = 17.71; p < 0.001). Altogether, 84.6% (44/52) of the respondents did not use protective measures. We described a sudden increase in malaria incidence in a rural, predominantly tea tribe population group with high illiteracy rate and ignorance on protective measures against malaria. More efforts that are concerted needed to educate the community about malaria control practices.

Utility of Indian Fruits in Cancer Prevention and Treatment: Time to Undertake Translational and Bedside Studies.

The World Health Organization predicts a 70% increase in cancer incidents in developing nations over the next decade, and it will be the second leading cause of death worldwide. Traditional plant-based medicine systems play an important role against various diseases and provide health care to a large section of the population in developing countries. Indigenous fruits and their bioactive compounds with beneficial effects like antioxidant, antiproliferative, and immunomodulatory are shown to be useful in preventing the incidence of cancer. India is one of the biodiversity regions and is native to numerous flora and fauna in the world. Of the many fruiting trees indigenous to India, Mango (Mangifera indica), Black plum (Eugenia jambolana or Syzygium jambolana), Indian gooseberry (Emblica officinalis or Phyllanthus emblica), kokum (Garcinia indica or Brindonia indica), stone apple or bael (Aegle marmelos), Jackfruit (Artocarpus heterophyllus), Karaunda (Carissa carandas) and Phalsa (Grewia asiatica), Monkey Jackfruit (Artocarpus lakoocha) and Elephant apple (Dillenia indica) have been shown to be beneficial in preventing cancer and in the treatment of cancer in validated preclinical models of study. In this review, efforts are also made to collate the fruits' anticancer effects and the important phytochemicals. Efforts are also made to address the underlying mechanism/s responsible for the beneficial effects of these fruits in cancer prevention and treatment. These fruits have been a part of the diet, are non-toxic, and easily acceptable for human application. The plants and some of their phytochemicals possess diverse medicinal properties. The authors propose that future studies should be directed at detailed studies with various preclinical models of study with both composite fruit extract/juice and the individual phytochemicals. Additionally, translational studies should be planned with the highly beneficial, well-investigated and pharmacologically multifactorial amla to understand its usefulness as a cancer preventive in the high-risk population and as a supportive agent in cancer survivors. The outcome of both preclinical and clinical studies will be useful for patients, the healthcare fraternity, pharmaceutical, and agro-based sectors.

Paricalcitol Attenuates Metabolic Syndrome-Associated Heart Failure through Enhanced Mitochondrial Fusion.

Objectives: Transition from cardiac hypertrophy to failure involves adverse metabolic reprogramming involving mitochondrial dysfunction. We have earlier shown that vitamin D deficiency induces heart failure, at least in part, through insulin resistance. However, whether activation of vitamin D receptor (VDR) can attenuate heart failure and underlying metabolic phenotype requires investigation. Thus, we aimed to assess the cardioprotective potential of paricalcitol, a vitamin D receptor-activator, against cardiac hypertrophy and failure in high-fat high-fructose-fed rats. Methods: Male Sprague Dawley rats were fed control (Con) or high-fat high-fructose (HFHFrD) diet for 20 weeks. After 12 weeks, rats from HFHFrD group were divided into the following: HFHFrD, HFHFrD+P (paricalcitol i.p. 0.08 µg/kg/day) and HFHFrD+E (enalapril maleate i.p. 10 mg/kg/day). Intraperitoneal glucose tolerance test, blood pressure measurement, and 2D echocardiography were performed. Cardiac fibrosis was assessed by Masson's trichrome staining of paraffin-embedded heart sections. Mitochondrial DNA and proteins, and citrate synthase activity were measured in rat hearts. VDR was silenced in H9c2 cardiomyoblasts, and immunoblotting was performed. Results: Paricalcitol improved glucose tolerance, serum lipid profile, and blood pressure in high-fat high-fructose-fed rats. Paricalcitol reduced cardiac wall thickness and increased ejection fraction in high-fat high-fructose-fed rats but had no effect on perivascular fibrosis. PGC1-α was upregulated in the HFHFrD+P group compared to the HFHFrD group, but there was no significant difference in mitochondrial content. Citrate synthase activity was significantly higher in the HFHFrD+P group compared to the HFHFrD group. Rat hearts of the HFHFrD+P group had significantly higher expression of mitofusins. H9c2 cells with VDR knockdown showed significantly lower expression of Mfn2. Improvement in the HFHFrD+P group was comparable with that in the HFHFrD+E group. Conclusions: Paricalcitol reverses cardiac dysfunction in rats with metabolic syndrome by enhancing mitochondrial fusion. We demonstrate repurposing potential of the drug currently used in end-stage kidney disease.

Dopamine ß hydroxylase as a potential drug target to combat hypertension.

INTRODUCTION: Despite a large number of commercially available drugs, hypertension and related cardiovascular diseases remain a global problem. It is thus imperative that novel drugs and therapeutic strategies are regularly identified, and alternative targets explored. Dopamine ß hydroxylase (DBH), a key player in the catecholamine biosynthetic pathway, may provide a therapeutic opportunity and should be extensively explored as a target for potent anti-hypertensives. Inhibitors of DBH have been successful in combating hypertension, as evidenced by the outcome of clinical trials for etamicastat and zamicastat. AREAS COVERED: We shed light on the strategies employed to identify inhibitors of the enzyme and outline the advantages that the target might offer. Structural and functional details of the enzyme are described along with specific methodologies for drug discovery that were never utilized for the therapeutic target. EXPERT OPINION: Effective inhibitors of the enzyme may be identified with computer-aided structure-based design. Adoption of new methodologies and the assessment of newly designed inhibitors in DBH-specific animal models will provide new, safe, and cost-effective therapeutic opportunities.

Vitamin D Deficiency in Rats Causes Cardiac Dysfunction by Inducing Myocardial Insulin Resistance.

SCOPE: Cause-effect relationship between vitamin D deficiency and cardiometabolic abnormalities remains undefined. The aim is to investigate the role of vitamin D deficiency in cardiac failure, through possible involvement in myocardial insulin signaling. METHODS AND RESULTS: Male SD rats (n = 6) are fed a normal diet (Con), vitamin D-deficient diet [Con(-)], or high-fat, high fructose diet (HFHFrD) for 20 weeks. Cardiac hypertrophy and fetal gene program are confirmed in Con(-) group. Cardiac dysfunction is assessed by echocardiography. Elevated renin, TGF-ß and collagen-1α mRNAs, p-ERK1/2, and perivascular fibrosis indicate cardiac remodeling in Con(-) group. Increased serum insulin, triglycerides, and blood pressure, and decreased glucose tolerance and HDL cholesterol are observed in Con(-) rats. Decreased p-Akt/Akt, GLUT4, SOD2, and catalase, and increased NF-κB, TNF-α, and IL-6 are observed in Con(-) hearts. In H9c2 cells, calcitriol attenuates palmitate-induced insulin resistance. VDR-silenced H9c2 cells show reduced Akt phosphorylation, GLUT4 translocation, and 2-NBDG uptake. Findings in Con(-) and HFHFrD groups are comparable. CONCLUSION: Vitamin D deficiency in rats mimic high-fat-, high-fructose-induced metabolic syndrome and cardiac dysfunction. This study demonstrates that vitamin D deficiency is an independent risk factor for heart failure, at least in part, through induction of myocardial insulin resistance.

Beneficial effects of fenofibrate in pulmonary hypertension in rats.

Pulmonary hypertension (PH) is a morbid complication of cardiopulmonary as well as several systemic diseases in humans. It is rapidly progressive and fatal if left untreated. In the present study, we investigated the effect of PPARα agonist fenofibrate (FF) on monocrotaline (MCT)-induced PH in rats. FF, because of its pleiotropic property, could be helpful in reducing inflammation, oxidative stress, and reactive oxygen species. On day 1, MCT (50 mg/kg, s.c.) was given to all the rats in MCT, sildenafil, and FF group except normal control rats. After 3 days of giving MCT, sildenafil (175 µg/kg, orally) and FF (120 mg/kg, orally) were given for 25 days. Echocardiography, hemodynamic parameters, fulton's index, histopathology, oxidative stress parameters, inflammatory markers, Bcl2/Bax gene expression ratio in the right ventricle, and protein expression for NOX-1 in lungs were studied in all the groups. FF has shown to prevent decrease in ratio of pulmonary artery acceleration time to ejection time, increase in ratio of right ventricular outflow tract dimension to aortic outflow dimension, rise in right ventricular systolic pressure, right ventricular hypertrophy, increase in the percentage medial wall thickness (%MWT), increase in oxidative stress and inflammation, increase in NADPH oxidase-1 (NOX-1) expression, and decrease in mRNA expression of Bcl2/Bax ratio caused by MCT. To conclude, FF prevented MCT-induced PH in rats by various mechanisms. It might be helpful in preventing PH in patients who are likely to develop PH.

Beneficial Effect of Ocimum sanctum (Linn) against Monocrotaline-Induced Pulmonary Hypertension in Rats.

BACKGROUND: The study was designed to explore any beneficial effect of Ocimum sanctum (Linn) (OS) in experimental pulmonary hypertension (PH) in rats. OS is commonly known as “holy basil” and “Tulsi” and is used in the Indian System of Medicine as antidiabetic, antioxidant, hepatoprotective, adaptogenic, and cardioprotective. METHODS: Monocrotaline (MCT) administration caused development of PH in rats after 28 days and rats were observed for 42 days. Treatments (sildenafil; 175 µg/kg, OS; 200 mg/kg) were started from day 29 after the development of PH and continued for 14 days. Parameters to assess the disease development and effectiveness of interventions were echocardiography, right and left ventricular systolic pressures, and right ventricular end diastolic pressure, percentage medial wall thickness (%MWT) of pulmonary artery, oxidative stress markers in lung tissue, NADPH oxidase (Nox-1) protein expression in lung, and mRNA expression of Bcl2 and Bax in right ventricular tissue. RESULTS: OS (200 mg/kg) treatment ameliorated increased lung weight to body weight ratio, right ventricular hypertrophy, increased RVSP, and RVoTD/AoD ratio. Moreover, OS treatment decreases Nox-1 expression and increases expression of Bcl2/Bax ratio caused by MCT. CONCLUSION: The present study demonstrates that OS has therapeutic ability against MCT-induced PH in rat which are attributed to its antioxidant effect. The effect of OS was comparable with sildenafil.

Proteomic analysis of the protective effects of aqueous bark extract of Terminalia arjuna (Roxb.) on isoproterenol-induced cardiac hypertrophy in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Aqueous bark extract of Terminalia arjuna (TA) has been in use as an ethnomedicine for cardiovascular ailments in the Indian subcontinent for centuries. Studies using hemodynamic, ROS scavenging and anti-inflammatory parameters in animal models have shown its anti-atherogenic, hypotensive, inotropic, anti-inflammatory effects. However, details analysis on its effects on established molecular and cell biological markers are a prerequisite for its wider acceptance to the medical community. AIMS OF THE STUDY: To test the efficacy of TA extract in ameliorating cardiac hypertrophy induced by ISO in rats. METHODS: Cardiac hypertrophy was induced by ISO (5mg/kg/day s.c. for 14 days) in rats and a standardized aqueous extract of TA stem bark was orally administered by gavage. Total RNA and protein were isolated from control, ISO, ISO plus TA and TA treated rat hearts and analyzed for the transcripts for the markers of hypertrophy, signaling kinases, transcription factors and total protein profile. RESULTS: TA extract reversed the induction of fetal genes like ß-myosin heavy chain, skeletal α-actin and brain natriuretic peptide in hypertrophic rat hearts. While ISO slightly increased the level of phospho-ERK, TA repressed it to about one third of the base line level. Survival kinase Akt, ER stress marker Grp78 and epigenetic regulator HDAC5 were augmented by ISO and TA restored them by various extents. ISO administration moderately increased the transcription factor NFκB binding activity, while coadministration of TA further increased it. AP-1 binding activity was largely unchanged by ISO treatment but it was upregulated when administered along with TA. MEF2D binding activity was increased by ISO and TA restored it to the baseline level. Global proteomic analysis revealed that TA treatment restored a subset of proteins up- and down-regulated in the hypertrophied hearts. Amongst those restored by TA were purinergic receptor X, myosin light chain 3, tropomyosin, and kininogen; suggesting a nodal role of TA in modulating cardiac function. CONCLUSIONS: This study for the first time reveals that TA partially or completely restores the marker mRNAs, signaling kinases, transcription factors and total protein profile in rat heart, thereby demonstrating its efficacy in preventing ISO-induced cardiac hypertrophy.

Beneficial effects of aqueous extract of stem bark of Terminalia arjuna (Roxb.), An ayurvedic drug in experimental pulmonary hypertension.

ETHNOPHARMACOLOGICAL RELEVANCE: The stem bark of Terminalia arjuna (Roxb.) is widely used in Ayurveda in various cardiovascular diseases. Many animal and clinical studies have validated its anti-ischemic, antihypertensive, antihypertrophic and antioxidant effects. Pulmonary hypertension (PH) is a fatal disease which causes right ventricular hypertrophy and right heart failure. Pulmonary vascular smooth muscle hypertrophy and increased oxidative stress are major pathological features of PH. As available limited therapeutic options fail to reduce the mortality associated with PH, alternative areas of therapy are worth exploring for potential drugs, which might be beneficial in PH. AIM OF THE STUDY: The effect of a standardised aqueous extract of the stem bark of Terminalia arjuna (Roxb.) in preventing monocrotaline (MCT)-induced PH in rat was investigated. MATERIALS AND METHODS: The study was approved by Institutional Animal Ethics Committe. Male Wistar rats (150-200g) were randomly distributed into five groups; Control, MCT (50mg/kg subcutaneously once), sildenafil (175µg/kg/day three days after MCT for 25 days), and Arjuna extract (TA125 and TA250 mg/kg/day orally after MCT for 25 days). PH was confirmed by right ventricular weight to left ventricular plus septum weight (Fulton index), right ventricular systolic pressure (RVSP), echocardiography, percentage medial wall thickness of pulmonary arteries (%MWT). Oxidative stress in lung was assessed by super oxide dismutase (SOD), catalase, reduced glutathione (GSH) and thiobarbituric acid reactive substance (TBARS). The protein expressions of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX-1) in lung and gene expression of Bcl2 and Bax in heart were analyzed by Western blot and RT PCR respectively. RESULTS: MCT caused right ventricular hypertrophy (0.58±0.05 vs 0.31±0.05; P<0.001 vs. control) and increase in RVSP (33.5±1.5 vs 22.3±4.7mm of Hg; P<0.001). Both sildenafil and Arjuna prevented hypertrophy and RVSP. Pulmonary artery acceleration time to ejection time ratio in echocardiography was decreased in PH rats (0.49±0.05 vs 0.32±0.06; P<0.001) which was prevented by sildenafil (0.44±0.06; P<0.01) and TA250 (0.45±0.06; P<0.01). % MWT of pulmonary arteries was increased in PH and was prevented by TA250. Increase in TBARS (132.7±18.4 vs 18.8±1.6nmol/mg protein; P<0.001) and decrease in SOD (58.4±14.1 vs 117.4±26.9U/mg protein; P<0.001) and catalase (0.30±0.05 vs 0.75±0.31U/mg protein; P<0.001) were observed in lung tissue of PH rats, which were prevented by sildenafil and both the doses of Arjuna extract. Protein expression of NOX1 was significantly increased in lung and gene expression of Bcl2/Bax ratio was significantly decreased in right ventricle in MCT-induced PH, both were significantly prevented by Arjuna and sildenafil. CONCLUSIONS: Aqueous extract of Terminalia arjuna prevented MCT-induced pulmonary hypertension which may be attributed to its antioxidant as well as its effects on pulmonary arteriolar wall thickening.

α-Amyrin attenuates high fructose diet-induced metabolic syndrome in rats.

This study investigated the effect of α-amyrin (a pentacyclic triterpene) on high-fructose diet (HFD)-induced metabolic syndrome in rats. Male Wistar rats were randomly distributed into different groups. The control group was fed normal rat chow diet. The HFD group was fed HFD (60%; w/w) for 42 days. Pioglitazone (10 mg/kg, orally, once daily) was used as a standard drug. α-Amyrin was administered in 3 doses (50, 100, and 200 mg/kg, orally, once daily along with HFD). Plasma glucose, total cholesterol, triglycerides, and high-density lipoprotein cholesterol (HDL-C) were estimated. Changes in blood pressure, oral glucose tolerance, and insulin tolerance were measured. Hepatic oxidative stress as well as messenger RNA (mRNA) and protein levels of peroxisome proliferator-activated receptor alpha (PPAR-α) were analyzed. A significant increase in systolic blood pressure, plasma glucose, total cholesterol, and plasma triglycerides and a significant decrease in HDL-C were observed in HFD rats as compared with control rats. Glucose tolerance and insulin tolerance were also significantly impaired with HFD. α-Amyrin prevented these changes in a dose-dependent manner. Hepatic oxidative stress as well as micro- and macrovesicular fatty changes in hepatocytes caused by HFD were also attenuated by α-amyrin. α-Amyrin preserved the hepatic mRNA and protein levels of PPAR-α, which was reduced in HFD group. This study thus demonstrates that α-amyrin attenuates HFD-induced metabolic syndrome in rats.

Anticonvulsant activity of the antidepressant drug, tianeptine, against pentylenetetrazole-induced seizures mitigates cognitive impairment in rats.

Treatment of depression, a common comorbidity in patients with epilepsy, is restricted as certain antidepressants are considered to be proconvulsants. In contrast, anticonvulsant effects have been reported with some antidepressants. In the present study, the effect of tianeptine, an antidepressant, was evaluated against pentylenetetrazole (PTZ)-induced seizures, cognitive impairment and oxidative stress in rats. Tianeptine was administered in three doses (20, 40 and 80 mg/kg) 30 min before PTZ (60 mg/kg, intraperitoneally). MK801, an N-methyl-D-aspartate antagonist, and naloxone, an opioid receptor antagonist, were administered with tianeptine to evaluate the involvement of N-methyl-D-aspartate and opioid receptors, respectively. Morris water maze, elevated plus maze and passive avoidance tests were performed for behavioural assessment. Brain malondialdehyde and reduced glutathione levels were estimated as markers of oxidative stress. Tianeptine showed dose-dependent protection against PTZ seizures. Coadministration of tianeptine with MK801 potentiated the anticonvulsant effect of tianeptine. The protective effect of tianeptine against PTZ seizures was mitigated when tianeptine was administered with naloxone. Impairment of learning and memory by PTZ was prevented by tianeptine. Tianeptine also attenuated the seizure-induced increased oxidative stress. Thus, tianeptine showed an anticonvulsant effect along with amelioration of seizure-induced cognitive impairment and oxidative stress. Hence, tianeptine could be a useful drug in epileptic patients with depression, with the advantage of having both antidepressant and antiepileptic effects.

Protective effect of thymoquinone against high-fructose diet-induced metabolic syndrome in rats.

PURPOSE: Thymoquinone (TQ), a bioactive constituent of Nigella sativa (Linn.) seed, which is commonly used as a spice in Asian food, has been reported to possess a wide range of biological effects. The present study evaluated the effect of TQ on high-fructose diet (HFD)-induced metabolic syndrome (MetS) in male Wistar rats. METHODS: MetS was induced by 60% HFD over 42 days. TQ (25, 50 and 100 mg/kg, p.o. once daily) was administered along with HFD for 42 days. Pioglitazone (10 mg/kg, p.o. once daily) was used as a standard drug. Plasma glucose, triglycerides, total cholesterol and HDL-cholesterol were estimated on days 0 and 42. Change in blood pressure, oral glucose tolerance and insulin resistance were measured. Hepatic thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase levels were estimated as measures of hepatic oxidative stress. Hepatic mRNA of PPAR-α and PPAR-γ was also studied. RESULTS: TQ prevented the characteristic features of HFD-induced MetS, such as hyperglycaemia, hypertriglyceridemia, hypercholesterolaemia and elevated systolic blood pressure. TQ also prevented impaired glucose tolerance and insulin resistance. It also ameliorated HFD-induced increase in hepatic TBARS and depletion of SOD, catalase and GSH. TQ prevented reduction in hepatic mRNA of PPAR-α and PPAR-γ in HFD rats, and the effects were comparable to those of pioglitazone. CONCLUSIONS: This study demonstrates protective effect of TQ against HFD-induced MetS on rats which might have been mediated via PPAR mechanism.

Genistein prevents isoproterenol-induced cardiac hypertrophy in rats.

Genistein, an isoflavone and a rich constituent of soy, possesses important regulatory effects on nitric oxide (NO) synthesis and oxidative stress. Transient and low release of NO by endothelial nitric oxide synthase (eNOS) has been shown to be beneficial, while high and sustained release by inducible nitric oxide synthase (iNOS) may be detrimental in pathological cardiac hypertrophy. The present study was designed to evaluate whether genistein could prevent isoproterenol-induced cardiac hypertrophy in male Wistar rats (150-200 g, 10-12 weeks old) rats. Isoproterenol (5 mg·(kg body weight)(-1)) was injected subcutaneously once daily for 14 days to induced cardiac hypertrophy. Genistein (0.1 and 0.2 mg·kg(-1), subcutaneous injection once daily) was administered along with isoproterenol. Heart tissue was studied for myocyte size and fibrosis. Myocardial thiobarbituric acid reactive substances (TBARS), glutathione (GSH), superoxide dismutase (SOD), catalase levels, and 1-OH proline (collagen content) were also estimated. Genistein significantly prevented any isoproterenol-induced increase in heart weight to body weight ratio, left ventricular mass (echocardiographic), myocardial 1-OH proline, fibrosis, myocyte size and myocardial oxidative stress. These beneficial effects of genistein were blocked by a nonselective NOS inhibitor (L-NAME), but not by a selective iNOS inhibitor (aminoguanidine). Thus, the present study suggests that the salutary effects of genistein on isoproterenol-induced cardiac hypertrophy may be mediated through inhibition of iNOS and potentiation of eNOS activities.