Effects of Phytochemicals on Blood Pressure and Neuroprotection Mediated Via Brain Renin-Angiotensin System

To Explore the Putative Molecular Targets of Diabetic Nephropathy and their Inhibition Utilizing Potential Phytocompounds

BACKGROUND

This review critically addresses the putative molecular targets of Diabetic Nephropathy (DN) and screens effective phytocompounds that can be therapeutically beneficial, and highlights their mechanistic modalities of action.

INTRODUCTION

DN has become one of the most prevalent complications of clinical hyperglycemia, with individual-specific variations in the disease spectrum that leads to fatal consequences. Diverse etiologies involving oxidative and nitrosative stress, activation of polyol pathway, inflammasome formation, Extracellular Matrix (ECM) modifications, fibrosis, and change in dynamics of podocyte functional and mesangial cell proliferation adds up to the clinical complexity of DN. Current synthetic therapeutics lacks target-specific approach, and is associated with the development of inevitable residual toxicity and drug resistance. Phytocompounds provides a vast diversity of novel compounds that can become an alternative therapeutic approach to combat the DN.

METHODS

Relevant publications were searched and screened from research databases like GOOGLE SCHOLAR, PUBMED and SCISEARCH. Out of 4895 publications, the most relevant publications were selected and included in this article.

RESULT

This study critically reviews over 60 most promising phytochemical and provides with their molecular targets, that can be of pharmacological significance in context to current treatment and concomitant research in DN.

CONCLUSION

This review highlights those most promising phytocompounds that have the potential of becoming new safer naturally-sourced therapeutic candidates and demands further attention at clinical level.

The effects of curcumin-piperine supplementation on inflammatory, oxidative stress and metabolic indices in patients with ischemic stroke in the rehabilitation phase: a randomized controlled trial

BACKGROUND

Stroke is a leading cause of death worldwide, which is associated with a heavy economic and social burden. The purpose of this study was to investigate the effects of supplementation with curcumin-piperine combination in patients with ischemic stroke in the rehabilitation stage.

METHODS

In this randomized controlled trial, 66 patients with stroke were randomized into two groups receiving curcumin-piperine tablets (500 mg curcumin + 5 mg piperine) and matched placebo tablets for 12 weeks. High-sensitivity C-reactive protein (hs-CRP), carotid intima-media thickness (CIMT), thrombosis, total antioxidant capacity (TAC), lipid profile, anthropometric indices, blood pressure, and quality of life were assessed before and after the intervention. Statistical data analysis was done using SPSS22 software.

RESULTS

A total of 56 patients with a mean age of 59.80 ± 4.25 years completed the trial. Based on ANCOVA test, adjusted for baseline values, curcumin-piperine supplementation for 12 weeks resulted in significant reductions in serum levels of hs-CRP (p = 0.026), total cholesterol (TC) (p = 0.009), triglycerides (TG) (p = 0.001), CIMT (p = 0.002), weight (P = 0.001), waist circumference (p = 0.024), and systolic and diastolic blood pressure (p < 0.001), and a significant increase in TAC (p < 0.001) in comparison to the placebo. Pain score significantly increased in both groups; however, its increase was significantly higher in the placebo group compared with the intervention group (p = 0.007). No significant changes were observed between the two groups in terms of serum fibrinogen, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and quality of life indices.

CONCLUSION

Curcumin-piperine supplementation had beneficial effects on CIMT, serum hs-CRP, TC, TG, TAC, and systolic and diastolic blood pressure in patients with ischemic stroke in the rehabilitation stage.

The effect of curcumin on blood pressure and cognitive impairment in spontaneously hypertensive rats

BACKGROUND/OBJECTIVES

It is known that the renin-angiotensin system (RAS) in the brain could regulate cognitive functions as well as blood pressure. Inhibition of RAS for the improvement of cognitive function may be a new strategy, but studies so far have mostly reported on the effects of RAS inhibition by drugs, and there is no research on cognitive improvement through RAS inhibition of food ingredients. Therefore, this study investigated the effect of curcumin on blood pressure and cognitive function and its related mechanism in spontaneously hypertensive rat/Izm (SHR/Izm).

MATERIALS/METHODS

Six-week-old SHR/Izm rats were divided into 5 groups: control group (CON), scopolamine group (SCO, drug for inducing cognitive deficits), positive control (SCO and tacrine [TAC]), curcumin 100 group (CUR100, SCO + Cur 100 mg/kg), and curcumin 200 group (CUR200, SCO + Cur 200 mg/kg). Changes in blood pressure, RAS, cholinergic system, and cognitive function were compared before and after cognitive impairment.

RESULTS

The SCO group showed increased blood pressure and significantly reduced cognitive function based on the y-maze and passive avoidance test. Curcumin treatments significantly improved blood pressure and cognitive function compared with the SCO group. In both the CUR100 and CUR200 groups, the mRNA expressions of angiotensin-converting enzyme (ACE) and angiotensin II receptor type1 (AT1), as well as the concentrations of angiotensin II (Ang II) in brain tissue were significantly decreased. The mRNA expression of the muscarinic acetylcholine receptors (mAChRs) and acetylcholine (ACh) content was significantly increased, compared with the SCO group.

CONCLUSIONS

The administration of curcumin improved blood pressure and cognitive function in SCO-induced hypertensive mice, indicating that the cholinergic system was improved by suppressing RAS and AT1 receptor expression and increasing the mAChR expression.

Are South African Wild Foods the Answer to Rising Rates of Cardiovascular Disease?

The rising burden of cardiovascular disease in South Africa gives impetus to managerial changes, particularly to the available foods in the market. Since there are many economically disadvantaged groups in urban societies who are at the forefront of the CVD burden, initiatives to make healthier foods available should focus on affordability in conjunction with improved phytochemical diversity to incentivize change. The modern obesogenic diet is deficient in phytochemicals that are protective against the metabolic products of sugar metabolism, i.e., inflammation, reactive oxygen species and mitochondrial fatigue, whereas traditional southern African food species have high phytochemical diversity and are also higher in soluble dietary fibres that modulate the release of sugars from starches, nurture the microbiome and produce digestive artefacts that are prophylactic against cardiovascular disease. The examples of indigenous southern African food species with high horticultural potential that can be harvested sustainably to feed a large market of consumers include: Aloe marlothii, Acanthosicyos horridus, Adansonia digitata, Aloe ferox, Amaranthus hybridus, Annesorhiza nuda, Aponogeton distachyos, Bulbine frutescens, Carpobrotus edulis, Citrullus lanatus, Dioscorea bulbifera, Dovyalis caffra, Eleusine coracana, Lagenaria siceraria, Mentha longifolia, Momordica balsamina, Pelargonium crispum, Pelargonium sidoides, Pennisetum glaucum, Plectranthus esculentus, Schinziophyton rautanenii, Sclerocarya birrea, Solenostemon rotundifolius, Talinum caffrum, Tylosema esculentum, Vigna unguiculata and Vigna subterranea. The current review explains the importance of phytochemical diversity in the human diet, it gives a lucid explanation of phytochemical groups and links the phytochemical profiles of these indigenous southern African foods to their protective effects against cardiovascular disease.

Effect of Bacillus coagulans SNZ 1969 on the Improvement of Bowel Movement in Loperamide-Treated SD Rats

Bacillus coagulans SNZ 1969 (B. coagulans SNZ 1969) is a spore-forming bacterium reported to be effective in attenuating constipation. However, there is no study on whether B. coagulans SNZ 1969 could improve constipation through mucin secretion and changes in intestinal hormones. To address this knowledge gap, rats were orally administrated with various treatments for four weeks. The normal control (NOR) group received saline only. There were four constipation-induced groups. The LOP group received only loperamide (LOP), a constipation-inducing agent. The BIS group received both LOP and Bisacodyl (BIS, a constipation treatment agent). The SNZ-L group received both LOP and B. coagulans SNZ 1969 at 1 × 10⁸ CFU/day. The SNZ-H group received LOP and B.coagulans SNZ 1969 at 1 × 10¹⁰ CFU/day. As indicators of constipation improvement, fecal pellet weight, fecal water content, gastrointestinal transit time, and intestinal motility were measured. Mucus secretion in the colon was determined by histological colon analysis and mucin-related gene expressions. Gastrointestinal (GI) hormones were also measured. SNZ-L and SNZ-H groups showed significantly increased fecal weights, fecal water contents, and intestinal motility than the LOP group. SNZ-L and SNZ-H groups also showed higher secretion of mucin in the colon and mRNA expression levels of Mucin 2 and Aquaporin 8 than the LOP group. The SNZ-H group showed significantly increased substance P but significantly decreased somatostatin and vasoactive intestinal peptide than the LOP group. The results of this study suggest that B. coagulans SNZ 1969 intake could attenuate constipation through mucin secretion and alteration of GI hormones.

Conducting the RBD of SARS-CoV-2 Omicron Variant with Phytoconstituents from Euphorbia dendroides to Repudiate the Binding of Spike Glycoprotein Using Computational Molecular Search and Simulation Approach

(1) Background: Natural constituents are still a preferred route for counteracting the outbreak of COVID-19. Essentially, flavonoids have been found to be among the most promising molecules identified as coronavirus inhibitors. Recently, a new SARS-CoV-2 B.1.1.529 variant has spread in many countries, which has raised awareness of the role of natural constituents in attempts to contribute to therapeutic protocols. (2) Methods: Using various chromatographic techniques, triterpenes (1–7), phenolics (8–11), and flavonoids (12–17) were isolated from Euphorbia dendroides and computationally screened against the receptor-binding domain (RBD) of the SARS-CoV-2 Omicron variant. As a first step, molecular docking calculations were performed for all investigated compounds. Promising compounds were subjected to molecular dynamics simulations (MD) for 200 ns, in addition to molecular mechanics Poisson–Boltzmann surface area calculations (MM/PBSA) to determine binding energy. (3) Results: MM/PBSA binding energy calculations showed that compound 14 (quercetin-3-O-β-D-glucuronopyranoside) and compound 15 (quercetin-3-O-glucuronide 6″-O-methyl ester) exhibited strong inhibition of Omicron, with ΔG_binding of −41.0 and −32.4 kcal/mol, respectively. Finally, drug likeness evaluations based on Lipinski’s rule of five also showed that the discovered compounds exhibited good oral bioavailability. (4) Conclusions: It is foreseeable that these results provide a novel intellectual contribution in light of the decreasing prevalence of SARS-CoV-2 B.1.1.529 and could be a good addition to the therapeutic protocol.

Utilizing preclinical models of genetic diversity to improve translation of phytochemical activities from rodents to humans and inform personalized nutrition

Mouse models are an essential tool in different areas of research, including nutrition and phytochemical research. Traditional inbred mouse models have allowed the discovery of therapeutical targets and mechanisms of action and expanded our knowledge of health and disease. However, these models lack the genetic variability typically found in human populations, which hinders the translatability of the results found in mice to humans. The development of genetically diverse mouse models, such as the collaborative cross (CC) or the diversity outbred (DO) models, has been a useful tool to overcome this obstacle in many fields, such as cancer, immunology and toxicology. However, these tools have not yet been widely adopted in the field of phytochemical research. As demonstrated in other disciplines, use of CC and DO models has the potential to provide invaluable insights for translation of phytochemicals from rodents to humans, which are desperately needed given the challenges and numerous failed clinical trials in this field. These models may prove informative for personalized use of phytochemicals in humans, including: predicting interindividual variability in phytochemical bioavailability and efficacy, identifying genetic loci or genes governing response to phytochemicals, identifying phytochemical mechanisms of action and therapeutic targets, and understanding the impact of genetic variability on individual response to phytochemicals. Such insights would prove invaluable for personalized implementation of phytochemicals in humans. This review will focus on the current work performed with genetically diverse mouse populations, and the research opportunities and advantages that these models can offer to phytochemical research.

Nutraceuticals and Herbs in Reducing the Risk and Improving the Treatment of COVID-19 by Targeting SARS-CoV-2

The worldwide transmission of acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as a deadly or devastating disease is known to affect thousands of people every day, many of them dying all over the planet. The main reason for the massive effect of COVID-19 on society is its unpredictable spread, which does not allow for proper planning or management of this disease. Antibiotics, antivirals, and other prescription drugs, necessary and used in therapy, obviously have side effects (minor or significant) on the affected person, there are still not clear enough studies to elucidate their combined effect in this specific treatment, and existing protocols are sometimes unclear and uncertain. In contrast, it has been found that nutraceuticals, supplements, and various herbs can be effective in reducing the chances of SARS-CoV-2 infection, but also in alleviating COVID-19 symptoms. However, not enough specific details are yet available, and precise scientific studies to validate the approved benefits of natural food additives, probiotics, herbs, and nutraceuticals will need to be standardized according to current regulations. These alternative treatments may not have a direct effect on the virus or reduce the risk of infection with it, but these products certainly stimulate the human immune system so that the body is better prepared to fight the disease. This paper aims at a specialized literary foray precisely in the field of these “cures” that can provide real revelations in the therapy of coronavirus infection

Potential use of polyphenols in the battle against COVID-19

The coronavirus disease 2019 (COVID-19) is a public health emergency of international concern. The rising number of cases of this highly transmissible infection has stressed the urgent need to find a potent drug. Although repurposing of known drugs currently provides an accelerated route to approval, there is no satisfactory treatment. Polyphenols, a major class of bioactive compounds in nature, are known for their antiviral activity and pleiotropic effects. The aim of this review is to assess the effects of polyphenols on COVID-19 drug targets as well as to provide a perspective on the possibility to use polyphenols in the development of natural approaches against this viral disease.