Therapeutic Potential of Centella asiatica and Its Triterpenes: A Review

A Mini-Review on Solid Lipid Nanoparticles and Nanostructured Lipid Carriers: Topical Delivery of Phytochemicals for the Treatment of Acne Vulgaris

Acne vulgaris (acne) is one of the most common dermatological problems affecting adolescents and young adults. Although acne may not lead to serious medical complications, its psychosocial effects are tremendous and scientifically proven. The first-line treatment for acne is topical medications composed of synthetic compounds, which usually cause skin irritation, dryness and itch. Therefore, naturally occurring constituents from plants (phytochemicals), which are generally regarded as safe, have received much attention as an alternative source of treatment. However, the degradation of phytochemicals under high temperature, light and oxygen, and their poor penetration across the skin barrier limit their application in dermatology. Encapsulation in lipid nanoparticles is one of the strategies commonly used to deliver drugs and phytochemicals because it allows appropriate concentrations of these substances to be delivered to the site of action with minimal side effects. Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) are promising delivery systems developed from the combination of lipid and emulsifier. They have numerous advantages that include biocompatibility and biodegradability of lipid materials, enhancement of drug solubility and stability, ease of modulation of drug release, ease of scale-up, feasibility of incorporation of both hydrophilic and lipophilic drugs and occlusive moisturization, which make them very attractive carriers for delivery of bioactive compounds for treating skin ailments such as acne. In this review, the concepts of SLNs and NLCs, methods of preparation, characterization, and their application in the encapsulation of anti-acne phytochemicals will be discussed.

Identification of Asiaticoside from Centella erecta (Apiaceae) as Potential Apyrase Inhibitor by UF-UHPLC-MS and Its In Vivo Antischistosomal Activity

Schistosomiasis, caused by parasites of the genus Schistosoma, is a neglected disease with high global prevalence, affecting more than 240 million people in several countries. Praziquantel (PZQ) is the only drug currently available for the treatment. S. mansoni NTPDases (known as SmNTPDases, ATP diphosphohydrolases or ecto-apyrases) are potential drug targets for the discovery of new antischistosomal drugs. In this study, we screen NTPDases inhibitors from Centella erecta (Apiaceae) using an ultrafiltration combined UHPLC-QTOF-MS method and potato apyrase, identifying asiaticoside as one of the apyrase-binding compounds. After isolation of asiaticoside from C. erecta extract, we assessed its in vivo antischistosomal activities against Schistosoma mansoni worms and its in vitro enzymatic apyrase inhibition. Also, molecular docking analysis of asiaticoside against potato apyrase, S. mansoni NTPDases 1 and 2 were performed. Asiaticoside showed a significant in vitro apyrase inhibition and molecular docking studies corroborate with its possible actions in potato apyrase and S. mansoni NTPDases. In mice harboring a patent S. mansoni infection, a single oral dose of asiaticoside (400 mg/kg. p.o.) showed significantly in vivo antischistosomal efficacy, markedly decreasing the total worm load and egg burden, giving support for further exploration of apyrase inhibitors as antischistosomal agents.

Asiaticoside Combined With Carbon Ion Implantation to Improve the Biocompatibility of Silicone Rubber and to Reduce the Risk of Capsule Contracture

Capsular contracture caused by silicone rubber is a critical issue in plastic surgery that urgently needs to be solved. Studies have shown that carbon ion implant in silicone rubber (carbon silicone rubber, C-SR) can significantly improve the capsular structure, but the effect of this improvement only appear 2months or later. In this study, asiaticoside combined with carbon silicone rubber was used to explore the changes in the capsule to provide a reference for the treatment of capsule contracture. Human fibroblasts (HFF-1) were used for in vitro experiments. The combined effect of asiaticoside and carbon silicone rubber on cell proliferation was determined by the CCK8 method, cell migration changes were measured by Transwell assays, cell cycle changes were measured by flow cytometry, and the expression levels of fibroblast transformation markers (vimentin and α-SMA), collagen (Col-1A1) and TGF-β/Smad signaling pathway-related proteins (TGF-β1, TβRI, TβRII and Smad2/3) were detected by immunofluorescence. In vivo experiments were carried out by subcutaneous implantation of the material in SD rats, and asiaticoside was oral administered simultaneously. WB and ELISA were used to detect changes in the expression of TGF-β/Smad signaling pathway-related proteins. TGF-β/Smad signaling pathway proteins were then detected and confirmed by HE, Masson and immunohistochemical staining. The results shown that asiaticoside combined with carbon ion implantation inhibited the viability, proliferation and migration of fibroblasts on silicone rubber. In vitro immunofluorescence showed that the secretion levels of α-SMA and Col-1A1 were significantly decreased, the transformation of fibroblasts into myofibroblasts was weakened, and the TGF-β/Smad signaling pathway was inhibited. In vivo experimental results showed that asiaticoside combined with carbon silicone rubber inhibited TGF-β1 secretion and inhibited the TGF-β/Smad signaling pathway, reducing the thickness of the capsule and collagen deposition. These results imply that carbon silicone rubber combined with asiaticoside can regulate the viability, proliferation and migration of fibroblasts by inhibiting the TGF-β/Smad signaling pathway and reduce capsule thickness and collagen deposition, which greatly reduces the incidence of capsule contracture.

In silico, in vitro screening of plant extracts for anti-SARS-CoV-2 activity and evaluation of their acute and sub-acute toxicity

BACKGROUND

In the absence of a specific drug for COVID 19, treatment with plant extracts could be an option worthy of further investigation and has motivated to evaluate the safety and anti-SARS-CoV-2 activity of plant extracts.

PURPOSE

To screen the phytochemicals for anti-SARS-CoV-2 in silico and evaluate their safety and efficacy in vitro and in vivo.

METHOD

The phytochemicals for anti-SARS-CoV-2 were screened in silico using molecular docking. The hits generated from in silico screening were subjected for extraction, isolation and purification. The anti-SARS-CoV-2 activity of Zanthoxylum piperitum (E1), Withania somnifera (E2), Calophyllum inophyllum (E3), Andrographis paniculata (E4), Centella asiatica (E5) ethanol extracts. The aerial parts were used for E1, E3, E4, E5 and root was used for E2. The in vitro safety and anti-SARS-CoV-2 activity of plant methanol extracts were performed in VeroE6 cells using Remdesivir as positive control. The acute and sub-acute toxicity study was performed in Wistar male and female rats.

RESULTS

The percentage of cell viability for E4, E5 and E2 treated VeroE6 cells were remarkably good on the 24th and 48th hour of treatment. The in vitro anti-SARS-CoV-2 activity of E4, E5 and E2 were significant for both E gene and N gene. The percentage of SARS-CoV-2 inhibition for E4 was better than Remdesivir. For E gene and N gene, Remdesivir showed IC₅₀ of 0.15 µM and 0.11 µM respectively, For E gene and N gene, E4 showed IC₅₀ of 1.18 µg and 1.16 µg respectively. Taking the clue from in vitro findings, the E4, E5 and E2 were combined (E 4.5.2) and evaluated for acute and sub-acute toxicity in Wistar male and female rats. No statistically significant difference in haematological, biochemical and histopathological parameters were noticed.

CONCLUSION

The study demonstrated the anti-SARS-CoV-2 activity in vitro and safety of plant extracts in both in vitro and in vivo experimental conditions.

Centella asiatica extract protects against cisplatin-induced hepatotoxicity via targeting oxidative stress, inflammation, and apoptosis

This study was designed to investigate the protective effects of Centella asiatica (CA) on cisplatin-induced hepatotoxicity and to clarify the underlying mechanism by biochemical, molecular, immunohistochemical, and histopathological analyses. Rats were pre-treated with two doses of CA (100 and 200 mg/kg, p.o.) for 14 consecutive days. Then, on the 15th day, hepatotoxicity was induced by a single cisplatin injection (10 mg/kg i.p.). On the 18th day, the rats were euthanized. CA effectively alleviated cisplatin-induced hepatic injury via reduction in AST, ALT, and ALP enzymes and a decrease in oxidative stress (decreased MDA and ROS, and increased SOD, CAT, and GSH). CA also mitigated the inflammatory damage by the inhibition of TNF-α, IL-1β, and NF-κB. The liver expression of caspase-3 and Bax was downregulated, while Bcl-2 was upregulated. Moreover, immunohistochemical results confirmed the recovery with CA by downregulation of iNOS and 8-OHdG expression. These results showed that with its antioxidant, anti-inflammatory, and anti-apoptotic activities, CA could help alleviate the hepatotoxic effects of cisplatin chemotherapy.

Ameliorative effect of gel combination of Centella asiatica extract transfersomes and rosemary essential oil nanoemulsion against UVB-induced skin aging in Balb/c mice

Background: Ultraviolet B (UVB) radiation induces physiological and morphological photoaging of the skin resulting in wrinkles, and loss of elasticity. This study analyzed nanoencapsulation of a gel combination of Centella asiatica (CA) transfersomes and rosemary essential oil (REO) nanoemulsion with lipid-based nanocarriers for the ability of both biological compounds to synergistically prevent UVB radiation, along with ameliorative and anti-aging effects. Methods: To ensure the quality, lipid-based nanocarriers of transfersomes and nanoemulsion were characterized based on physicochemical properties such as particle size distribution, polydispersity index, zeta potential. In vivo studies were used to determine the biological effects of a gel combination of CA transfersomes, and REO nanoemulsion applied topically two weeks before UVB radiation (840 mJ/cm2) in BALB/c hairless mice. Results: Results showed that the optimum lipid-based nanocarriers had a particle size of 43.97 ± 5.6 nm, a polydispersity index of 0.64 ± 0.01, and a zeta potential of -10.91 ± 1.99 mV. In vivo experiments revealed that topical application of a gel combination of CA transfersomes and REO nanoemulsion significantly ameliorated wrinkle formation, epidermal hyperplasia, and collagen fiber arrangement caused by UVB exposure. Further, the gel combining CA transfersomes and REO nanoemulsion suppressed lipid peroxidation by decreasing the expression of malondialdehyde (MDA) and collagen destruction by inhibiting matrix metalloproteinase-9 (MMP-9) expression. Moreover, the gel combination of CA transfersomes and REO nanoemulsion upregulated type I collagen through activation of the transforming growth factor-β (TGF-β)/Smad pathway, thereby recovering the density of collagen fiber reduced by UVB radiation. Conclusions: Overall, these data indicate that topical application of a gel combination of CA transfersomes and REO nanoemulsion could act synergistically and potentially prevents oxidative stress and collagen degradation in the skin from UVB-induced photoaging.

Phytochemical profile of Centevita®, a Centella asiatica leaves extract, and isolation of a new oleanane-type saponin

Centella asiatica is a popular medicinal plant and several phytotherapic products in the market include its extracts as active constituents. A LC-MS guided phytochemical investigation on the commercial C. asiatica leaves extract named Centevita® allowed characterization and quantification of 24 secondary metabolites including 10 polyphenols and 14 ursane- or oleanane-type triterpenoids in the sapogenin or saponin form. This metabolomic analysis, besides confirming that the triterpenoid fraction roughly accounts for 45% of the extract weight, also resulted in the discovery of isoterminoloside, a new triglycoside saponin of the unprecedented 2α,3β,6β,23-tetrahydroxyolean-13(18)-en-28-oic acid (isoterminolic acid). The structure of isoterminoloside was characterized by a detailed ESI-MS and NMR investigation.

Increase water solubility of Centella asiatica extract by indigenous bioenhancers could improve oral bioavailability and disposition kinetics of triterpenoid glycosides in beagle dogs

A newly standardised extract of Centellaasiatica (Centell-S) with better water solubility than the previous standardised extract of C.asiatica (ECa 233) was developed, and pharmacokinetic profiles of bioactive triterpenoids were investigated in beagle dogs. The test substances were administered via intravenous or oral administration with single and multiple doses for 7 days. The concentrations of major bioactive triterpenoids, including madecassoside, asiaticoside, madecassic acid, and asiatic acid, in biological samples were measured by liquid chromatography–tandem mass spectrometry. The dogs in this study showed good tolerability to all test substances, based on the physical appearance and blood chemistry 24 h after dosing. The major bioactive triterpenoids found in systemic blood circulation were madecassoside, asiaticoside, and asiatic acid; the concentration of these components ranged from 1 to 10,000 µg/L after intravenous administration of 1.0 mg/kg Centell-S. Oral administration of 10 and 20 mg/kg Centell-S generated approximately twofold higher plasma levels of both madecassoside and asiaticoside compared with equivalent doses of ECa 233. In addition, there was an accumulation of triterpenoid glycosides after multiple oral administrations of Centell-S for 7 days, while triterpenic acids showed little tendency for accumulation. Beagles had good tolerability to both standardised extracts of C.asiatica, and showed a similar pattern of bioactive triterpenoids to humans. Centell-S increased oral bioavailability of major triterpenoid glycosides and can be further developed into a phytopharmaceutical product.

Pharmacokinetics and Pharmacodynamics of Key Components of a Standardized Centella asiatica Product in Cognitively Impaired Older Adults: A Phase 1, Double-Blind, Randomized Clinical Trial

Centella asiatica is reputed in Eastern medicine to improve cognitive function in humans. Preclinical studies have demonstrated that aqueous extracts of C. asiatica improve cognition in mouse models of aging and Alzheimer's disease (AD) through the modulation of mitochondrial biogenesis and nuclear factor-erythroid-2-related factor 2 (Nrf2)-dependent antioxidant response genes. This randomized, double-blind, crossover Phase I trial explored the oral bioavailability and pharmacokinetics of key compounds from two doses (2 g and 4 g) of a standardized C. asiatica aqueous extract product (CAP), over 10 h, in four mildly demented older adults on cholinesterase inhibitor therapy. The analysis focused on triterpenes (TTs) and caffeoylquinic acids (CQAs), which are known to contribute to C. asiatica's neurological activity. The acute safety of CAP and the effects on NRF2 gene expression in peripheral blood mononuclear cells were evaluated. Single administration of 2 g or 4 g of CAP was safe and well-tolerated. The TT aglycones, asiatic acid and madecassic acid, were identified in plasma and urine, while the parent glycosides, asiaticoside and madecassoside, although abundant in CAP, were absent in plasma and had limited renal excretion. Similarly, mono- and di-CQAs showed delayed absorption and limited presence in plasma or urine, while the putative metabolites of these compounds showed detectable plasma pharmacokinetic profiles and urinary excretion. CAP elicited a temporal change in NRF2 gene expression, mirroring the TT aglycone's pharmacokinetic curve in a paradoxical dose-dependent manner. The oral bioavailability of active compounds or their metabolites, NRF2 target engagement, and the acute safety and tolerability of CAP support the validity of using CAP in future clinical studies.

Developing a Rational, Optimized Product of Centella asiatica for Examination in Clinical Trials: Real World Challenges

Botanical products are frequently sold as dietary supplements and their use by the public is increasing in popularity. However, scientific evaluation of their medicinal benefits presents unique challenges due to their chemical complexity, inherent variability, and the involvement of multiple active components and biological targets. Translation away from preclinical models, and developing an optimized, reproducible botanical product for use in clinical trials, presents particular challenges for phytotherapeutic agents compared to single chemical entities. Common deficiencies noted in clinical trials of botanical products include limited characterization of the product tested, inadequate placebo control, and lack of rationale for the type of product tested, dose used, outcome measures or even the study population. Our group has focused on the botanical Centella asiatica due to its reputation for enhancing cognition in Eastern traditional medicine systems. Our preclinical studies on a Centella asiatica water extract (CAW) and its bioactive components strongly support its potential as a phytotherapeutic agent for cognitive decline in aging and Alzheimer's disease through influences on antioxidant response, mitochondrial activity, and synaptic density. Here we describe our robust, scientific approach toward developing a rational phytotherapeutic product based on Centella asiatica for human investigation, addressing multiple factors to optimize its valid clinical evaluation. Specific aspects covered include approaches to identifying an optimal dose range for clinical assessment, design and composition of a dosage form and matching placebo, sourcing appropriate botanical raw material for product manufacture (including the evaluation of active compounds and contaminants), and up-scaling of laboratory extraction methods to available current Good Manufacturing Practice (cGMP) certified industrial facilities. We also address the process of obtaining regulatory approvals to proceed with clinical trials. Our study highlights the complexity of translational research on botanicals and the importance of identifying active compounds and developing sound analytical and bioanalytical methods for their determination in botanical materials and biological samples. Recent Phase I pharmacokinetic studies of our Centella asiatica product in humans (NCT03929250, NCT03937908) have highlighted additional challenges associated with designing botanical bioavailability studies, including specific dietary considerations that need to be considered.

The Role of Cyclodextrins in the Design and Development of Triterpene-Based Therapeutic Agents

Triterpenic compounds stand as a widely investigated class of natural compounds due to their remarkable therapeutic potential. However, their use is currently being hampered by their low solubility and, subsequently, bioavailability. In order to overcome this drawback and increase the therapeutic use of triterpenes, cyclodextrins have been introduced as water solubility enhancers; cyclodextrins are starch derivatives that possess hydrophobic internal cavities that can incorporate lipophilic molecules and exterior surfaces that can be subjected to various derivatizations in order to improve their biological behavior. This review aims to summarize the most recent achievements in terms of triterpene:cyclodextrin inclusion complexes and bioconjugates, emphasizing their practical applications including the development of new isolation and bioproduction protocols, the elucidation of their underlying mechanism of action, the optimization of triterpenes’ therapeutic effects and the development of new topical formulations.

Anti-Planktonic and Anti-Biofilm Properties of Pentacyclic Triterpenes-Asiatic Acid and Ursolic Acid as Promising Antibacterial Future Pharmaceuticals

Due to the ever-increasing number of multidrug-resistant bacteria, research concerning plant-derived compounds with antimicrobial mechanisms of action has been conducted. Pentacyclic triterpenes, which have a broad spectrum of medicinal properties, are one of such groups. Asiatic acid (AA) and ursolic acid (UA), which belong to this group, exhibit diverse biological activities that include antioxidant, anti-inflammatory, diuretic, and immunostimulatory. Some of these articles usually contain only a short section describing the antibacterial effects of AA or UA. Therefore, our review article aims to provide the reader with a broader understanding of the activity of these acids against pathogenic bacteria. The bacteria in the human body can live in the planktonic form and create a biofilm structure. Therefore, we found it valuable to present the action of AA and UA on both planktonic and biofilm cultures. The article also presents mechanisms of the biological activity of these substances against microorganisms.

Withania somnifera and Centella asiatica Extracts Ameliorate Behavioral Deficits in an In Vivo Drosophila melanogaster Model of Oxidative Stress

Due to an increase in the aging population, age-related diseases and age-related changes, such as diminished cognition and sleep disturbances, are an increasing health threat. It has been suggested that an increase in oxidative stress underlies many of these changes. Current treatments for these diseases and changes either have low efficacy or have deleterious side effects preventing long-time use. Therefore, alternative treatments that promote healthy aging and provide resilience against these health threats are needed. The herbs Withania somnifera and Centella asiatica may be two such alternatives because both have been connected with reducing oxidative stress and could therefore ameliorate age-related impairments. To test the effects of these herbs on behavioral phenotypes induced by oxidative stress, we used the Drosophila melanogaster sniffer mutant which has high levels of oxidative stress due to reduced carbonyl reductase activity. Effects on cognition and mobility were assessed using phototaxis assays and both, W. somnifera and C. asiatica water extracts improved phototaxis in sniffer mutants. In addition, W. somnifera improved nighttime sleep in male and female sniffer flies and promoted a less fragmented sleep pattern in male sniffer flies. This suggests that W. somnifera and C. asiatica can ameliorate oxidative stress-related changes in behavior and that by doing so they might promote healthy aging in humans.

Thermal resistance and high-performance microwave decontamination assessment of Bacillus endospores isolated from food-grade herbal extracts

Generally, endospore contamination can occur from different sources during product manufacturing in many industries and therefore lower its quality by affecting physicochemical properties and shelf-life. Bacterial endospores can germinate inside the product and produce several enzymes, which can cause several undesirable changes. This study assessed the spores thermal resistance and applied a microwave decontamination technique toward herbal extracts (Tilia tomentosa and Centella asiatica) containing ethanol or glycerol. Based on 16S rRNA analysis, the detected contaminant endospores belonged to different Bacillus species, namely B. subtilis, B. zhangzhouensis, and B. pumilus. The thermal resistance assessment using inoculated endospores in the actual products revealed B. pumilus T2 as the most resistant endospore to the heat treatments tested in both T. tomentosa and C. asiatica extracts. Finally, a high-performance microwave technique was used to decontaminate T. tomentosa extract against the mixture of Bacillus spores. Results from the microwave technique indicate that the increase of temperature from 100°C to 105°C not only decontaminated the product but also could dramatically decrease the effective thermal treatment time (10 times), which can benefit the product quality. The results provided in this study considerably contribute to improving an original decontamination method for products containing glycerol and ethanol with the most negligible effect on product quality.

Short-Term Effects of Supplemental L-Arginine, Diosmin, Troxerutin, and Hesperidin in Diabetic Patients: A Pilot Study

Background and Aims

Inflammatory, oxidative stress, and endothelial dysfunction play a key role in the pathogenesis of long-term cardiovascular complications in patients with diabetes. The present observational prospective study is aimed at evaluating the effects of micronutrients and phytochemicals contained in the dietary supplement Flebotrofine® (AMNOL Chimica Biologica) on biochemical markers of inflammation, endothelial dysfunction, and glycemic control in patients with diabetes.

Methods

105 type 1 or type 2 diabetes patients regularly took a daily dose of the dietary supplement Flebotrofine® for three consecutive months, and haematological and biochemical parameters were checked at baseline, after three months of treatment, and one month after its suspension. Statistical comparison of the laboratory parameters was performed using the two-tailed ANOVA test for repeated samples with a statistical significance level set at p < 0.05.

Results

The daily use of Flebotrofine® did not change the glycemic metabolic compensation of enrolled patients. After three months of regular Flebotrofine® intake, the plasma levels of the antioxidant β-carotene and of arginine were significantly higher compared with the baseline values, with a decrease in the ADMA/arginine ratio. In contrast, apolipoprotein B, ApoB/ApoA1 ratio, and platelet and leukocyte counts significantly dropped.

Conclusion

The daily use of Flebotrofine® might be a valid supplement of arginine, the precursor of NO, and essential in the prevention of endothelial dysfunction. The regular intake of arginine and phytochemicals also improved the antioxidant and antithrombotic profile of enrolled patients. Therefore, Flebotrofine® could be a useful dietary supplement to prevent long-term complications in patients with diabetes.

Pharmacological Effects of Centella asiatica on Skin Diseases: Evidence and Possible Mechanisms

The medicinal herb Centella asiatica (L.) Urban known as gotu kola has been reported to exhibit a wide range of pharmacological activities. In particular, a significant body of scientific research exists on the therapeutic properties of preparations of C. asiatica or its triterpenes in the treatment of skin diseases. The present study is aimed to provide a comprehensive overview of the beneficial effects of C. asiatica on skin diseases. Peer-reviewed articles on the potent dermatological effects of C. asiatica were acquired from PubMed, Web of Science, Scopus, ScienceDirect, and SciFinder. This review provides an understanding of pharmacological studies which confirm the potent dermatological effects and underlying molecular mechanisms of C. asiatica. This medicinal plant and its triterpenes include asiaticoside, madecassoside, and their aglycones, asiatic acid and madecassic acid. These compounds exert therapeutic effects on dermatological diseases such as acne, burns, atopic dermatitis, and wounds via NF-κB, TGF-β/Smad, MAPK, Wnt/β-catenin, and STAT signaling in in vitro and in vivo studies. However, additional rigorously controlled long-term clinical trials will be necessary to confirm the full potential of C. asiatica as a therapeutic agent.

Are Uropathogenic Bacteria Living in Multispecies Biofilm Susceptible to Active Plant Ingredient-Asiatic Acid?

Urinary tract infections (UTIs) are a serious health problem in the human population due to their chronic and recurrent nature. Bacteria causing UTIs form multispecies biofilms being resistant to the activity of the conventionally used antibiotics. Therefore, compounds of plant origin are currently being searched for, which could constitute an alternative strategy to antibiotic therapy. Our study aimed to determine the activity of asiatic acid (AA) against biofilms formed by uropathogenic Escherichia coli, Enterobacter cloacae, and Pseudomonas aeruginosa. The influence of AA on the survival, biofilm mass formation by bacteria living in mono-, dual-, and triple-species consortia as well as the metabolic activity and bacterial cell morphology were determined. The spectrophotometric methods were used for biofilm mass synthesis and metabolic activity determination. The survival of bacteria was established using the serial dilution assay. The decrease in survival and a weakening of the ability to create biofilms, both single and multi-species, as well as changes in the morphology of bacterial cells were noticed. As AA works best against young biofilms, the use of AA-containing formulations, especially during the initial stages of infection, seems to be reasonable. However, there is a need for further research concerning AA especially regarding its antibacterial mechanisms of action.

Sensitive skin: Active ingredients on the spotlight

OBJECTIVE

Sensitive skin is characterized by self-reported sensory perceptions in response to stimuli that should not provoke unpleasant sensations. Cosmetic products for sensitive skin are designed to minimize these symptoms. This study aimed to unveil the most used active ingredients for sensitive skin in facial care products from the pharmacy and parapharmacy channel.

METHODS

A pool of products from the pharmacy and parapharmacy channel whose label included the expressions 'sensitive skin', 'reactive skin' or 'intolerant skin' were analysed. The active ingredients were identified from product compositions and ranked in descending order of occurrence. The scientific evidence regarding the mechanism of action and efficacy of each ingredient was also compiled.

RESULTS

Eighty-eight products from 19 multinational brands were included. Niacinamide leads the top, followed by Avena sativa, allantoin, glycyrrhetinic acid and derivatives and Laminaria ochroleuca. Ingredients that can reduce skin inflammation and act on the skin barrier were used in more than half of the products analysed. The clinical studies regarding the active ingredients used in these products remain sparse and lack methodological quality. Among the top ingredients, niacinamide, panthenol and acetyl dipeptide-1 cetyl ester were the only ones studied on volunteers having sensitive skin, while acetyl dipeptide-1 cetyl ester and palmitoyl tripeptide-8 were designed to act on the molecular targets involved in this condition.

CONCLUSION

This study reveals the most used active ingredients in cosmetic products for sensitive skin, as well as the scientific evidence supporting their efficacy and the mechanisms of action. This insight is meaningful for dermatologists and other health professionals to provide customized advice based on the symptomatology of individuals with sensitive skin, and for the formulation of cosmetic products and design of new active ingredients.

Chitosan/PEO nanofibers containing Calendula officinalis extract: Preparation, characterization, in vitro and in vivo evaluation for wound healing applications

Wound healing is a complex pathophysiological process, highlighting the importance of effective and thorough wound care along with the prevention of wound infection, a major barrier that can slow down or even disrupt the healing process. To date, there are plenty of herbal plants well known and historically supernatural, showing profound wound healing effects. Application of such herbal extracts/ingredients in electrospun nanofiber platforms has shown promising outcomes in improving wound healing process. Based on these facts, we loaded Calendula officinalis extract (CO) in chitosan/polyethylene oxide scaffolds (CS/PEO) by electrospinning. Using SEM, morphology of electrospun scaffolds showed a narrow range of fiber diameter, around 143--252 nm, with uniform and bead-free appearance. FT-IR spectroscopy confirmed the presence of CO extract in nanofibrous scaffolds. Of importance, incorporation of CO extract improved mechanical properties of CS/PEO nanofibers. A 1602 cP reduction in viscosity and a 0.892 ms/cm increase in the conductivity of the solution was observed after addition of the CO extract. CO extract showed strong antibacterial properties with 96% and 94% reduction in Gram positive and Gram negative bacteria, respectively. In vitro studies with fibroblast cells confirmed enhanced proliferation, growth and attachment of the cells. The in vivo and histological analysis of rat wounds, revealed excellent wound healing ability of CS/PEO/CO dressings (87.5 % wound closure after 14 days) via improving collagen synthesis, re-epithelization and remodeling of the tissue. In sum, our findings show that CS/PEO/CO scaffolds can be used as a promising dressing for the treatment of skin wounds.

Virtual screening of functional foods and dissecting their roles in modulating gene functions to support post COVID-19 complications

COVID‐19 has become the focal point since 2019 after the outbreak of coronavirus disease. Many drugs are being tested and used to treat coronavirus infections; different kinds of vaccines are also introduced as preventive measure. Alternative therapeutics are as well incorporated into the health guidelines of some countries. This research aimed to look into the underlying mechanisms of functional foods and how they may improve the long‐term post COVID‐19 cardiovascular, diabetic, and respiratory complications through their bioactive compounds. The potentiality of nine functional foods for post COVID‐19 complications was investigated through computational approaches. A total of 266 bioactive compounds of these foods were searched via extensive literature reviewing. Three highly associated targets namely troponin I interacting kinase (TNNI3K), dipeptidyl peptidase 4 (DPP‐4), and transforming growth factor beta 1 (TGF‐β1) were selected for cardiovascular, diabetes, and respiratory disorders, respectively, after COVID‐19 infections. Best docked compounds were further analyzed by network pharmacological tools to explore their interactions with complication‐related genes (MAPK1 and HSP90AA1 for cardiovascular, PPARG and TNF‐alpha for diabetes, and AKT‐1 for respiratory disorders). Seventy‐one suggested compounds out of one‐hundred and thirty‐nine (139) docked compounds in network pharmacology recommended 169 Gene Ontology (GO) items and 99 Kyoto Encyclopedia of Genes and Genomes signaling pathways preferably AKT signaling pathway, MAPK signaling pathway, ACE2 receptor signaling pathway, insulin signaling pathway, and PPAR signaling pathway. Among the chosen functional foods, black cumin, fenugreek, garlic, ginger, turmeric, bitter melon, and Indian pennywort were found to modulate the actions. Results demonstrate that aforesaid functional foods have attenuating roles to manage post COVID‐19 complications.

Hypoxia-Induced Neuroinflammation in Alzheimer's Disease: Potential Neuroprotective Effects of Centella asiatica

Alzheimer's disease (AD) is a neurodegenerative disorder that is characterised by the presence of extracellular beta-amyloid fibrillary plaques and intraneuronal neurofibrillary tau tangles in the brain. Recurring failures of drug candidates targeting these pathways have prompted research in AD multifactorial pathogenesis, including the role of neuroinflammation. Triggered by various factors, such as hypoxia, neuroinflammation is strongly linked to AD susceptibility and/or progression to dementia. Chronic hypoxia induces neuroinflammation by activating microglia, the resident immune cells in the brain, along with an increased in reactive oxygen species and pro-inflammatory cytokines, features that are common to many degenerative central nervous system (CNS) disorders. Hence, interests are emerging on therapeutic agents and plant derivatives for AD that target the hypoxia-neuroinflammation pathway. Centella asiatica is one of the natural products reported to show neuroprotective effects in various models of CNS diseases. Here, we review the complex hypoxia-induced neuroinflammation in the pathogenesis of AD and the potential application of Centella asiatica as a therapeutic agent in AD or dementia.

Asiatic acid inhibits angiogenesis and vascular permeability through the VEGF/VEGFR2 signaling pathway to inhibit the growth and metastasis of breast cancer in mice

Anti-angiogenic medicines have been evaluated as anticancer therapies, however, their use remains limited in clinical practice due to associated adverse effects. Asiatic acid (AA) is known to have broad-spectrum anticancer properties, however, its effects on angiogenesis in breast cancer remain to be fully established. In this study, we analyzed the inhibitory effects of AA on angiogenesis using human umbilical vein endothelial cells (HUVECs) cultured in vitro and on the growth and metastasis of a subcutaneous breast cancer 4T1 tumor model and a lung metastasis model in vivo. AA significantly inhibited HUVECs proliferation, migration, and tube formation in vitro. In vivo, AA significantly reduced the microvascular density and blood vascular permeability in breast cancer tumors and inhibited growth and lung metastasis. AA inhibited the expression of vascular endothelial growth factor (VEGF) in HUVECs and subsequently downregulated the phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2) and its downstream target proteins including ERK1/2, Src, and FAK. These results indicate that AA significantly inhibits angiogenesis and blood vessel permeability through the VEGF/VEGFR2 signal axis to inhibit the growth and metastasis of breast cancer. Our data strongly demonstrate the potential applications of AA in the treatment of breast cancer.

In silico identification of natural products from Centella asiatica as severe acute respiratory syndromecoronavirus 2 main protease inhibitor

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) main protease (S-CoV-2 Mpro) is one of the main targets in designing antiviral against SARS-CoV-2. Centella asiatica contains several triterpenoids, polyacetylenes, and benzoic ester derivative with various biological activities including anti-inflammation and antiviral. Triterpenoids from C. asiatica could act as inhibitors of S-CoV-2 Mpro. The main objective of this study was to identify potential natural products from C. asiatica as S-CoV-2 Mpro inhibitor with better pharmacokinetic through in silico molecular docking method. : As much as 11 compounds from C. asiatica were docked with S-CoV-2 Mpro (PDB ID: 6LU7) using AutoDock v4.2.6. Pharmacokinetic parameters of these compounds were assessed using SwissADME (free access webserver). Molecular docking results of 11 natural products indicated that asiatate 6 and asiatate 10 have strong interaction with quite similar binding free energy compared to native ligand (‒9.00 and‒9.58 kcal/mol compared to ‒9.18 kcal/mol, respectively) with proper interaction to the catalytic dyad (His41 and Cys145). Pharmacokinetic analysis revealed that asiatate 4, asiatate 10, and asiatate 11 have poor pharmacokinetic properties. These results indicated that asiatate 6 could be recommended for further study as S-CoV-2 Mpro inhibitor.

Therapeutic Promises of Medicinal Plants in Bangladesh and Their Bioactive Compounds against Ulcers and Inflammatory Diseases

When functioning properly, the stomach is the center of both physical and mental satisfaction. Gastrointestinal disorders, or malfunctioning of the stomach, due to infections caused by various biological entities and physiochemical abnormalities, are now widespread, with most of the diseases being inflammatory, which, depending on the position and degree of inflammation, have different names such as peptic or gastric ulcers, irritable bowel diseases, ulcerative colitis, and so on. While many synthetic drugs, such as non-steroidal anti-inflammatory drugs, are now extensively used to treat these diseases, their harmful and long-term side effects cannot be ignored. To treat these diseases safely and successfully, different potent medicinal plants and their active components are considered game-changers. In consideration of this, the present review aimed to reveal a general and comprehensive updated overview of the anti-ulcer and anti-inflammatory activities of medicinal plants. To emphasize the efficacy of the medicinal plants, various bioactive compounds from the plant extract, their experimental animal models, and clinical trials are depicted.

Insights into antioxidant activities and anti-skin-aging potential of callus extract from Centella asiatica (L.)

Formation of oxidative stress in dermal fibroblasts plays crucial roles in aging processes of skin. The use of phytochemicals that can promote capacity of fibroblasts to combat oxidative stress is an attractive strategy to prevent skin aging and promote skin beauty. Centella asiatica has been used to treat multitude of diseases for centuries. Previous investigations demonstrated that extracts from C. asiatica have a broad range of beneficial activities through their antioxidant activity. Hence, the extract from this medicinal plant could be a great candidate for anti-skin-aging agent. Callus culture offers a powerful platform for sustainable, rapid and large-scale production of phytochemicals to serve extensive demands of pharmaceutical and cosmeceutical industries. Here, we demonstrated the application of callus culture of Centella asiatica to produce bioactive metabolites. The 50% ethanolic extract of callus culture has distinctive features of chemical compositions and biological profiles. Information from HPTLC-DPPH and HPLC analysis suggested that the callus extract comprises distinctive antioxidant compounds, compared with those isolated from authentic plant. Moreover, results from cell culture experiment demonstrated that callus extract possesses promising antioxidant and anti-skin-aging activities. Pre-treatment with callus extract attenuated H₂O₂-induced-cytotoxicity on human dermal fibroblasts. The results from RT-qPCR clearly suggested that the upregulation of cellular antioxidant enzymes appeared to be major contributor for the protective effects of callus extract against oxidative stress. Moreover, supplementation with callus extract inhibited induction of matrix metalloprotease-9 following H₂O₂ exposure, suggesting its potential anti-skin-aging activity. Our results demonstrate the potential utility of C. asiatica callus extract as anti-skin-aging agent in cosmeceutical preparations.

Cosmetic and Dermatological Properties of Selected Ayurvedic Plant Extracts

Due to the constantly growing interest in ingredients of natural origin, this study attempts to evaluate the possibility of using extracts from three Ayurvedic plants in preparations for the care and treatment of skin diseases. Therefore, studies of antioxidant properties were carried out using DPPH and ABTS radicals, obtaining 76% and 88% of these radical scavenging, respectively. A significant decrease in the intracellular level of free radicals and an increase in the activity of the antioxidant enzyme-superoxide dismutase by almost 60% were also observed. In addition, the extracts were assessed for anti-inflammatory and anti-aging properties, obtaining over 70% inhibition of lipoxygenase activity and almost 40% of collagenase. Additionally, the cytoprotective properties of the obtained extracts on skin cells, keratinocytes and fibroblasts, were demonstrated. To assess the content of biologically active compounds, HPLC-electrospray ionization (ESI)-MS/MS multiple reaction monitoring (MRM) analyses were performed. The obtained results show that all three analyzed plants are a valuable source of biologically active substances with desired properties in the context of skin cell protection. Particularly noteworthy is the extract of Epilobium angustifolium L., for which the most promising results were obtained.

Madecassoside Inhibits Body Weight Gain via Modulating SIRT1-AMPK Signaling Pathway and Activating Genes Related to Thermogenesis

BACKGROUND

Pre-clinical research studies have shown that Madecassoside (MA) has favorable therapeutic effects on arthritis, acne, vitiligo and other diseases. However, the effects of MA on obesity have not yet been studied. This study mainly aimed to investigate the effects of MA in protecting against obesity and its underlying mechanism in reducing obesity.

METHODS

Obese diabetic KKay/TaJcl mice model was adopted to the study. The body weight of all animals was recorded daily, and the blood glucose, blood lipid, and serum aminotransferase levels were examined, respectively. The expression of P-AMPK, SIRT1, P-LKB1, P-ACC, and P-HSL in abdominal fat, mesenteric fat, and epididymal fat was measured by western blotting, and the levels of PPARα, CPT1a, PGC-1α, UCP-1, Cidea, Cox7a1, and Cox8b were examined by real-time quantitative PCR (RT-qPCR).

RESULTS

The results revealed that the body weight of the mice in MA group was significantly reduced, and the body mass index (BMI) showed significant difference between the two groups after 8 weeks of MA treatment. Further research revealed that it affected the mesenteric fat and epididymis fat by activating SIRT1/AMPK signaling pathway, and then promoted fatty acid oxidation of epididymal fat (PPARα ↑, CPT1a↑, and PGC-1α↑). Last but not the least, it also promoted the expression of UCP-1 and stimulated thermoregulatory genes (Cidea, Cox7a1, and Cox8b) in brown fat and mesenteric fat.

CONCLUSIONS

Taken together, these findings suggest that MA can inhibit the weight gain in obese diabetic mice, and reduce triglyceride levels, inhibit lipogenesis of mesenteric fat, promote epididymal fat lipolysis and fatty acid oxidation. Furthermore, MA treatment might promote mesenteric fat browning and activate mitochondrial function in brown fat as well as mesenteric fat.