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Bioactive phenolics can be found in abundance in Calophyllum species. Phytochemical studies are carried out on the stem bark of Calophyllum recurvatum and Calophyllum andersonii , which has led to the isolation and elucidation of phytochemicals, thwaitesixanthone (1), teysmanone A (2), soulattrolide (3), calanone (4), isocalanone (5) and friedelin (6), respectively. The cytotoxic activities of compounds (2), (3), (4) and (5) as well as plant extracts were tested against HeLa Chang liver, HepG2 and HL-7702 cell lines. Phenylpyranocoumarins, teysmanone A (2) and soulattrolide (3) portrayed appreciable cytotoxicity activities at 42.57 ± 1.20 and 34.53 ± 3.41 µg/mL, respectively against HepG2 cell line comparable to the positive control, curcumin. Meanwhile, n -hexane extract from C. recurvatum exhibited cytotoxicity with the IC 50 value of 36.43 ± 0.64 and 26.25 ± 4.83 µg/mL against HeLa Chang liver and HepG2 cell lines. All the tested compounds and plant extracts displayed non-cytotoxic properties on HL-7702 cell line.

Phytochemical investigation on the bark of E. kingiana plant afforded ten compounds, including six polyketides namely kingianin A 1 , kingianin B 2 , kingianin E 3 , kingianin F 4 , kingianin K 5 and kingianin L 6 , three endiandric acids; kingianic acid A 7 , tsangibeilin B 8 and endiandric acid M 9 , and one sesquiterpene; daibuoxide 10 . All compounds were separated as racemic mixture by recycling high-performance liquid chromatography (RHPLC), except for daibuoxide. Their structures were elucidated by detailed spectroscopic and comparative literature data analysis. This is the first report on the presence of the sesquiterpene; daibuoxide in Endiandra genus. In vitro enzymatic bio-evaluation of the isolated compounds against α -amylase and α -glucosidase showed that 4 demonstrated the best α -amylase and α -glucosidase inhibitory activity with IC 50 values of 181.54 ± 6.27 µg/mL and 237.87 ± 0.07 µg/mL, respectively. In addition, molecular docking analysis confirmed the α -amylase and α -glucosidase inhibitory activities demonstrated by 4 .

Genus Calophyllum from the family of Calophyllaceae is an evergreen broad-leaved tree that is endemic to Southeast Asia, especially Malaysia. They have been reported for various ethnomedicinal uses in traditional medicine. Previous studies of Malaysian Calophyllum species revealed them to be a rich source of bioactive phytoconstituents such as xanthones, coumarins, terpenoids, and chromanone acids. To date, the extracts and compounds from Malaysian Calophyllum species have shown a broad spectrum of pharmacological activities. For example, calanolide A, a coumarin isolated from Malaysian C. lanigerum , has now reached clinical development to become an anti-HIV drug. This article presents an overview of the significant phytochemical and pharmacological activities of Malaysian Calophyllum species to aid researchers in further discovery of potential benefits of various species of this genus.

Mitragynine, is a naturally occurring indole alkaloid that can be isolated from the leaves of a psychoactive medicinal plant. Mitragyna speciosa , also known as kratom, is found to possess promising analgesic effects on mediating the opioid receptors such as µ (MOR), δ (DOR), and κ (KOR). This alkaloid has therapeutic potential for pain management as it has limited adverse effect compared to a classical opioid, morphine. Mitragynine is frequently regarded to behave like an opioid but possesses milder withdrawal symptoms. The use of this alkaloid as the source of an analgesic candidate has been proven through comprehensive preclinical and clinical studies. The present data have shown that mitragynine is able to bind to opioid receptors, particularly MOR, to exhibit the analgesic effect. Moreover, the chemical and pharmacological aspects of mitragynine and its diastereomers, speciogynine, speciociliatine, and mitraciliatine, are discussed. It is interesting to know how the difference in stereochemical configuration could lead to the difference in the bioactivity of the respective compounds. Hence, in this review, the updated pharmacological and toxicological properties of mitragynine and its diastereomers are discussed to render a comprehensive understanding of the pharmacological properties of mitragynine and its diastereomers based on their structure-activity relationship study., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Karunakaran, Ngew, Zailan, Mian Jong and Abu Bakar.)

High fructose consumption has been linked to low-grade inflammation and insulin resistance that results in increased intracellular 11ß-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity. Celastrol, a pentacyclic triterpene, has been demonstrated to exhibit multifaceted targets to attenuate various metabolic diseases associated with inflammation. However, the underlying mechanisms by which celastrol exerts its attributive properties on high fructose diet (HFrD)-induced metabolic syndrome remain elusive. Herein, the present study was aimed to elucidate the mechanistic targets of celastrol co-administrations upon HFrD in rats and evaluate its potential to modulate 11β-HSD1 activity. Celastrol remarkably improved glucose tolerance, lipid profiles, and insulin sensitivity along with suppression of hepatic glucose production. In rat adipose tissues, celastrol attenuated nuclear factor-kappa B (NF-κB)-driven inflammation, reduced c-Jun N-terminal kinases (JNK) phosphorylation, and mitigated oxidative stress via upregulated genes expression involved in mitochondrial biogenesis. Furthermore, insulin signaling pathways were significantly improved through the restoration of Akt phosphorylation levels at Ser473 and Thr308 residues. Celastrol exhibited a potent, selective and specific inhibitor of intracellular 11β-HSD1 towards oxidoreductase activity (IC 50 value = 4.3 nM) in comparison to other HSD-related enzymes. Inhibition of 11β-HSD1 expression in rat adipose microsomes reduced the availability of its cofactor NADPH and substrate H6PDH in couple to upregulated mRNA and protein expressions of glucocorticoid receptor. In conclusion, our results underscore the most likely conceivable mechanisms exhibited by celastrol against HFrD-induced metabolic dysregulations mainly through attenuating inflammation and insulin resistance, at least via specific inhibitions on 11β-HSD1 activity in adipose tissues., (© 2021 International Union of Biochemistry and Molecular Biology.)

Background: The use of lycopene as a complementary medicine for Type II diabetes mellitus (T2DM) is limited and controversial. This study evaluated the effect of lycopene intake on the changes of glycaemic status and antioxidant capacity among the T2DM patients., Patients and Methods: This case-control study involved the participation of 87 patients and 122 healthy individuals. Lycopene intake was assessed by using a food frequency questionnaire. The peripheral antioxidant capacity among the T2DM patients was evaluated. Glycated haemoglobin (HbA1c) and fasting plasma glucose (FPG) were measured as indications of glycaemic status., Results: Peripheral antioxidant capacity was significantly lower in the T2DM group. Direct positive correlations were found between the lycopene intake and peripheral antioxidant level among the T2DM patients. Contrarily, HbA1c and FPG levels decreased significantly with the higher lycopene intake., Conclusions: T2DM patients with a higher lycopene intake showed a greater peripheral antioxidant capacity and better glycaemic control. Lycopene may act to ameliorate oxidative stress and improve the pathophysiology of T2DM.