Mallikarjuna Rao Pichika

Comparative antioxidant and anti-inflammatory effects of [6]-gingerol, [8]-gingerol, [10]-gingerol and [6]-shogaol

ETHNOPHARMACOLOGICAL RELEVANCE Zingiber officinale Rosc. (Zingiberaceae) has been traditionally used in Ayurvedic, Chinese and Tibb-Unani herbal medicines for the treatment of various illnesses that involve inflammation and which are caused by oxidative stress. Although gingerols and shogaols are the major bioactive compounds present in Zingiber officinale, their molecular mechanisms of actions and the relationship between their structural features and the activity have not been well studied. AIM OF THE STUDY The aim of the present study was to examine and compare the antioxidant and anti-inflammatory activities of gingerols and their natural analogues to determine their structure-activity relationship and molecular mechanisms. MATERIALS AND METHODS The in vitro activities of the compounds [6]-gingerol, [8]-gingerol, [10]-gingerol and [6]-shogaol were evaluated for scavenging of 1,1-diphenyl-2-picyrlhydrazyl (DPPH), superoxide and hydroxyl radicals, inhibition of N-formyl-methionyl-leucyl-phenylalanine (f-MLP) induced reactive oxygen species (ROS) production in human polymorphonuclear neutrophils (PMN), inhibition of lipopolysaccharide induced nitrite and prostaglandin E(2) production in RAW 264.7 cells. RESULTS In the antioxidant activity assay, [6]-gingerol, [8]-gingerol, [10]-gingerol and [6]-shogaol exhibited substantial scavenging activities with IC(50) values of 26.3, 19.47, 10.47 and 8.05 microM against DPPH radical, IC(50) values of 4.05, 2.5, 1.68 and 0.85 microM against superoxide radical and IC(50) values of 4.62, 1.97, 1.35 and 0.72 microM against hydroxyl radical, respectively. The free radical scavenging activity of these compounds also enhanced with increasing concentration (P<0.05). On the other hand, all the compounds at a concentration of 6 microM have significantly inhibited (P<0.05) f-MLP-stimulated oxidative burst in PMN. In addition, production of inflammatory mediators (NO and PGE(2)) has been inhibited significantly (P<0.05) and dose-dependently. CONCLUSIONS 6-Shogaol has exhibited the most potent antioxidant and anti-inflammatory properties which can be attributed to the presence of alpha,beta-unsaturated ketone moiety. The carbon chain length has also played a significant role in making 10-gingerol as the most potent among all the gingerols. This study justifies the use of dry ginger in traditional systems of medicine.

Chalcones with electron-withdrawing and electron-donating substituents: anticancer activity against TRAIL resistant cancer cells, structure-activity relationship analysis and regulation of apoptotic proteins.

In the present study, a series of 46 chalcones were synthesised and evaluated for antiproliferative activities against the human TRAIL-resistant breast (MCF-7, MDA-MB-231), cervical (HeLa), ovarian (Caov-3), lung (A549), liver (HepG2), colorectal (HT-29), nasopharyngeal (CNE-1), erythromyeloblastoid (K-562) and T-lymphoblastoid (CEM-SS) cancer cells. The chalcone 38 containing an amino (-NH2) group on ring A was the most potent and selective against cancer cells. The effects of the chalcone 38 on regulation of 43 apoptosis-related markers in HT-29 cells were determined. The results showed that 20 apoptotic markers (Bad, Bax, Bcl-2, Bcl-w, Bid, Bim, CD40, Fas, HSP27, IGF-1, IGFBP-4, IGFBP-5, Livin, p21, Survivin, sTNF-R2, TRAIL-R2, XIAP, caspase-3 and caspase-8) were either up regulated or down regulated.

Should a Toll-like receptor 4 (TLR-4) agonist or antagonist be designed to treat cancer? TLR-4: its expression and effects in the ten most common cancers

Toll-like receptor 4 (TLR-4) is well known for its host innate immunity. Despite the fact that TLR-4 activation confers antitumor responses; emerging evidence suggests that TLR-4 is associated with tumor development and progression. It is now clear that overactivation of TLR-4, through various immune mediators, may cause immune response dysfunction, resulting in tumorigenesis. Different cancers could have different extents of TLR-4 involvement during tumorigenesis or tumor progression. In this review, we focus on infection- and inflammation-related TLR-4 activation in noncancer and cancer cells, as well as on the current evidence about the role of TLR-4 in ten of the most common cancers, viz, head and neck cancer, lung cancer, gastrointestinal cancer, liver cancer, pancreatic cancer, skin cancer, breast cancer, ovarian cancer, cervical cancer, and prostate cancer.

6-Shogaol inhibits breast and colon cancer cell proliferation through activation of peroxisomal proliferator activated receptor γ (PPARγ).

6-Shogaol has been shown to possess many antitumor properties including inhibition of cancer cell growth, inhibition of cancer metastasis, induction of apoptosis in cancer cells and induction of cancer cell differentiation. Despite its prominent antitumor effects, the direct molecular target of 6-shogaol has remained elusive. To identify the direct targets of 6-shogaol, a comprehensive antitumor profile of 6-shogaol (NSC752389) was tested in the NCI-60 cell line in an in vitro screen. The results show that 6-shogaol is COMPARE negative suggesting that it functions via a mechanism of action distinct from existing classes of therapeutic agents. Further analysis using microarray gene profiling and Connectivity Map analysis showed that MCF-7 cells treated with 6-shogaol display gene expression signatures characteristic of peroxisome proliferator activated receptor γ (PPARγ) agonists, suggesting that 6-shogaol may activate the PPARγ signaling pathway for its antitumor effects. Indeed, treatment of MCF-7 and HT29 cells with 6-shogaol induced PPARγ transcriptional activity, suppressed NFκB activity, and induced apoptosis in breast and colon cancer cells in a PPARγ-dependent manner. Furthermore, 6-shogaol is capable of binding to PPARγ with a binding affinity comparable to 15-delta prostaglandin J2, a natural ligand for PPARγ. Together, our findings suggest that the antitumor effects of 6-shogaol are mediated through activation of PPARγ and imply that activation of PPARγ might be beneficial for breast and colon cancer treatment.

In vitro antibacterial effects of Cinnamomum extracts on common bacteria found in wound infections with emphasis on methicillin-resistant Staphylococcus aureus.

ETHNOPHARMACOLOGICAL RELEVANCE Cinnamomum species have been widely used in many traditional systems of medicine around the world. In the Malaysian traditional system of medicine, the leaves, stem bark and stem wood of Cinnamomum iners, Cinnamomum porrectum, Cinnamomum altissimum and Cinnamomum impressicostatum have been used to treat wound infections. To study the antibacterial effects of Cinnamomum iners, Cinnamomum porrectum, Cinnamomum altissimum and Cinnamomum impressicostatum against common bacteria found in wound infections with primary focus on methicillin-resistant Staphylococcus aureus (MRSA). MATERIALS AND METHODS The crude extracts from the leaves, stem-bark and stem-wood of Cinnamomum iners, Cinnamomum porrectum, Cinnamomum altissimum and Cinnamomum impressicostatum were obtained using sequential extraction with hexane, ethylacetate, methanol and water. The volatile oils were obtained by hydro-distillation. The antibacterial activities of extracts were investigated using disk diffusion assays and broth microdilution assays. RESULTS The volatile oils obtained from the stem-bark of Cinnamomum altissimum, Cinnamomum porrectum and Cinnamomum impressicostatum have shown significant antibacterial activity against a wide range of Gram positive and Gram negative bacteria including MRSA. A few test extracts have shown better activity against MRSA as compared to methicillin sensitive Staphylococcus aureus (MSSA). Amongst all the test extracts, Cinnamomum impressicostatum stem-bark water extract produced the largest inhibition zone of 21.0mm against MRSA while its inhibition zone against MSSA was only 8.5mm. The minimum inhibitory concentration (MIC) of this extract against MRSA was 19.5 μg mL(-1) and the corresponding minimum bactericidal concentration (MBC) was 39.0 μg mL(-1). CONCLUSIONS This study has scientifically validated the traditional use of Cinnamomum species in treating wound infections. Of high scientific interest was the observation that the antibacterial effect of Cinnamomum impressicostatum stem-bark crude water extract against MRSA was significantly higher than its effect against MSSA, suggesting that the extract contains a compound(s) with higher specific neutralising activity against the drug resistance markers of MRSA.

Basic Ionic Liquid [bmIm]OH–Mediated Gewald Reaction as Green Protocol for the Synthesis of 2-Aminothiophenes

Abstract A simple, efficient, and environmental friendly procedure was developed based on the Gewald reaction for the synthesis of 2-aminothiophenes using a basic ionic liquid [bmIm]OH as both catalyst and solvent. Besides being a green protocol, the method offers advantages of successful synthesis of a variety of alkyl, aryl, alkoxy, and alkylamino-2-aminothiophenes in good yields. GRAPHICAL ABSTRACT

Acute oral toxicity studies of Swietenia macrophylla seeds in Sprague Dawley rats

Background: Swietenia macrophylla King. (Meliaceae) seeds (SMS); commonly known as sky fruit and locally known in Malaysia as Tunjuk Langit; have been used in traditional Malay medicine for the treatment of diabetes and hypertension. The people eat only a tiny amount of raw seed, weighing not more than 5 mg. Aim: To evaluate the safety of Swietenia macrophylla seeds (SMS) at a single-dose oral administration of 2 g/kg body weight (bw) in sprague dawley (SD) rats. Materials and Methods: Eight-week old male and female SD rats were administered a single-oral dose of 2g/kg bw. The rats′ general behavior, and toxic signs were observed throughout the 14-day study period. The food and water intake by rats and their body weight were monitored during the study period. At the end of the study period, the relative weights of the organs (lung, liver, spleen, heart, kidney, testis, stomach); the hematological and biochemical parameters were measured; the architecture and histology of the organs (liver, kidney and lungs) were observed. Results: Oral administration of SMS to rats did not affect, either food or water intake; relative organ weight of vital organs; the hematological and biochemical parameters; did not show significant changes in the architecture and histology of vital organs. Overall, there were neither signs of toxicity nor deaths recorded during the study period. Conclusion: The rat dose of 2 g/kg bw is equivalent to the human dose of 325 mg/kg bw, which is well below the usual amount consumed by people, did not show any signs of toxicity in rats.

A comprehensive review on polyelectrolyte complexes

Global research on polyelectrolytes at a fundamental and applied level is intensifying because the advantages of sustainability are being accepted in academia and industrial research settings. During recent decades, polyelectrolytes became one of the most attractive subjects of scientific research owing to their great potential in the areas of advanced technologies. Polyelectrolytes are a type of polymer that have multitudinous ionizable functional groups. Ionized polyelectrolytes in solution can form a complex with oppositely charged polyelectrolytes - a polyelectrolyte complex (PEC). The present article provides a comprehensive review on PECs and their classification, theory and characterization, as well as a critical analysis of the current research.

Antimicrobial activity of Bauhinia tomentosa and Bauhinia vahlii roots

The hexane, ethylacetate and methanol extracts from Bauhinia tomentosa and Bauhinia vahlii roots were tested for their antimicrobial activity against Gram-positive bacteria (four strains), Gram-negative bacteria (three strains) and three fungi strains using microdilution methods, for the determination of minimal inhibition concentration (MIC) and the minimal microbicidal concentration (MMC). The MIC values of hexane extracts of B. tomentosa and B. vahlii roots were more than 250 µg/ml. The MIC values of ethylacetate and methanol extracts of B. tomentosa roots varied from 7.81 to 31.25 µg/ml and 31.25 to 62.50 µg/ml, respectively. The MIC values of ethylacetate and methanol extracts of B. vahlii roots varied from 15.63 to 62.5 µg/ml and 62.5 to 250 µg/ml, respectively. MMC values obtained are two times greater than the corresponding MIC values. The activities of ethylacetate extracts are attributed to the presence of flavonoids and that of methanol extracts are attributed to the presence of tannins.

An update on natural compounds in the remedy of diabetes mellitus: A systematic review

Herbal medicine, phytomedicine or botanical medicine are synonymous, utilizes plants intended for medicinal purposes. Medicinal use of herbal medicine in the treatment and prevention of diseases including diabetes has a long history compared to conventional medicine. Diabetes is one of the major public health concerns over the world. Diabetes or hyperglycemia is considered to be one of the common public health hazard; optimal control of which is still not possible. Persistent hyperglycemia or uncontrolled diabetes has the potential to cause serious complications such as kidney disease, vision loss, cardiovascular disease, and lower-limb amputations which contributed towards morbidity and mortality in diabetes. There are various approaches to treat and prevent diabetes as well as its secondary complications, one of it is herbal medicines. However, the selection of herbs might depends on several factors, which include the stage of progression of diabetes, types of comorbidities that the patients are having, availability, affordability as well as the safety profile of the herbs. This review focuses on the herbal and natural remedies that play the role in the treatment or prevention of this morbid disorder – diabetes, including their underlying mechanisms for the blood glucose-lowering property and the herbal products already been marketed for the remedial action of diabetes.