Phytochemical analysis and evaluation of antimicrobial, antioxidant, and antidiabetic activities of essential oils from Moroccan medicinal plants: Mentha suaveolens, Lavandula stoechas, and Ammi visnaga.

Mentha suaveolens, Lavandula stoechas, and Ammi visnaga are widely used in Moroccan folk medicine against several pathological disorders, including diabetes and infectious diseases. This work was designed to determine the chemical profile of M. suaveolens (MSEO), L. stoechas (LSEO), and A. visnaga (AVEO) essential oils and assess their antimicrobial, antioxidant, and antidiabetic effects. The volatile components of LSEO, AVEO, and MSEO were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). The in vitro antidiabetic activity was assessed using α-amylase and α-glucosidase enzymes, while DPPH, FRAP, and ß-carotene/linoleic acid methods were used to determine the antioxidant capacity. The antimicrobial activities were investigated using disc diffusion and broth-microdilution assays. GC-MS investigation revealed that the main components were fenchone (29.77 %) and camphor (24.9 %) for LSEO, and linalool (38.29 %) for AVEO, while MSEO was mainly represented by piperitenone oxide (74.55 %). The results of the antimicrobial evaluation showed that all examined essential oils (EOs) had noticeable antimicrobial activity against both bacteria and yeast, especially Micrococcus luteus and Bacillus subtilis. The MIC, MBC, and MFC values were ranged from 0.015 % to 0.5 %. The MBC/MIC and MFC/MIC ratios were less than or equal to 4.0 % (v/v), indicating their noticeable bactericidal and candidacidal efficacy. Moreover, the three EOs showed significant inhibitory effects on α-amylase and α-glucosidase (p < 0.05). It also exerted remarkable activity on FRAP, ß-carotene, and DPPH radicals. These findings demonstrated that the tested plants have promising biological activities, validating their ethnomedicinal value and providing potential applications as natural drugs.

Acceleration of Bone Fracture Healing through the Use of Bovine Hydroxyapatite or Calcium Lactate Oral and Implant Bovine Hydroxyapatite-Gelatin on Bone Defect Animal Model.

Bone grafts a commonly used therapeutic technique for the reconstruction and facilitation of bone regeneration due to fractures. BHA-GEL (bovine hydroxyapatite-gelatin) pellet implants have been shown to be able accelerate the process of bone repair by looking at the percentage of new bone, and the contact between the composite and bone. Based on these results, a study was conducted by placing BHA-GEL (9:1) pellet implants in rabbit femoral bone defects, accompanied by 500 mg oral supplement of BHA or calcium lactate to determine the effectiveness of addition supplements. The research model used was a burr hole defect model with a diameter of 4.2 mm in the cortical part of the rabbit femur. On the 7th, 14th and 28th days after treatment, a total of 48 New Zealand rabbits were divided into four groups, namely defect (control), implant, implant + oral BHA, and implant + oral calcium lactate. Animal tests were terminated and evaluated based on X-ray radiology results, Hematoxylin-Eosin staining, vascular endothelial growth Factor (VEGF), osteocalcin, and enzyme-linked immunosorbent assay (ELISA) for bone alkaline phosphatase (BALP) and calcium levels. From this research can be concluded that Oral BHA supplementation with BHA-GEL pellet implants showed faster healing of bone defects compared to oral calcium lactate with BHA-GEL pellet implants.

Carrageenophyte Kappaphycus malesianus Inhibits Microglia-Mediated Neuroinflammation via Suppression of AKT/NF-κB and ERK Signaling Pathways.

Neuroinflammation is an inflammatory response in any part of the central nervous system triggered by the activation of microglia and astrocytes to produce proinflammatory cytokines in the brain. However, overproduction of proinflammatory cytokines further contributes to the development of neurodegenerative disorders. Red seaweed, Kappaphycus malesianus, is a predominant carrageenophyte commercially cultivated in Semporna, Sabah, Malaysia. It is an important source of raw material for kappa-carrageenan productions in the food, pharmaceutical and cosmetics industries. However, no studies have been conducted focusing on the antineuroinflammatory effects of K. malesianus. The aim of the present study was to investigate the effect of the antineuroinflammatory activity of K. malesianus extracts (ethyl acetate, ethanol and methanol) on lipopolysaccharide-stimulated BV2 microglia and the underlying mechanisms involved in the regulation of neuroinflammatory pathways. Extract with the most promising antineuroinflammatory activity was analyzed using liquid chromatography-mass spectrometry (LC-MS). Our results show that methanol extract has a convincing antineuroinflammatory effect by suppressing both AKT/NF-κB and ERK signaling pathways to inhibit the expression of all proinflammatory cytokines without causing a cytotoxicity effect. LC-MS analysis of methanol extract revealed two compounds: prosopinine and eplerenone. Our findings indicated that metabolites of K. malesianus are potent antineuroinflammatory agents with respect to prevention of neurological disorders.

Production of the secondary metabolite catechin by in vitro cultures of Camellia sinensis L.

Background Catechin is one of the secondary metabolites in Camellia sinensis L. that is alternatively produced through in vitro cultures. The in vitro culture product is possibly improved by optimizing the culture medium with the addition of growth regulators and precursors. The purpose of this study was to confirm the success of the secondary catechin metabolite production through the in vitro culture of C. sinensis L in a relatively short time. Methods The secondary catechin metabolite product is obtained in about 40 days. The study was conducted by (1) leaf cutting for inoculation in Murashige and Skoog media with 1 µg/mL of 2,4-dichlorophenoxyacetic acid growth regulator; (2) the inoculation of callus multiplication on the same medium as a partially modified inoculation media condition with the addition of 1 µg/mL of 6-benzylaminopurine (BAP) and 2 µg/mL of 2,4-dichlorophenoxyacetic acid at concentration; (3) callus multiplication developed on a new medium containing phenylalanine precursors (300 µg/mL); (4) testing growth by harvesting the callus and weighing the wet weight of its biomass and (5) identification of the callus qualitatively and quantitatively by using high-performance liquid chromatography (HPLC). Results The level of secondary catechin metabolite produced was 2.54 µg/mL and 12.13 µg/mL in solid and suspension media, respectively. Conclusions It is concluded that the method is effective and efficient in producing catechin product from C. sinensis L.

Attenuation of IL-1ß on the use of glucosamine as an adjuvant in meloxicam treatment in rat models with osteoarthritis.

Background Osteoarthritis (OA) is the most prevalent joint disease and a common cause of joint pain, functional loss, and disability. The severity of this disease is always associated with increased levels of proinflammatory cytokines, which play an important role in cartilage damage, synovitis, and other damage to joint tissues. The discovery that many soluble mediators such as cytokines or prostaglandins can increase the production of matrix metalloproteinases by chondrocytes led to the first steps of an inflammatory state. Several studies show that cytokines, such as interleukin 1ß, have a major role in the development of inflammation that occurs in these joints. The use of glucosamine as an adjuvant to meloxicam therapy is expected to inhibit the development of inflammatory OA. Methods The OA model in rat was induced by single injection of intraarticular monosodium iodoacetate (MIA). The development of OA was observed for 21 days. Furthermore, the evaluation of glucosamine potency as an adjuvant of meloxicam therapy for reducing IL-1ß was done by combined treatment at a low dose of meloxicam 1 mg/kg BW with glucosamine at a dose of 125, 250, or 500 mg/kg BW orally for 28 days. Response to hyperalgesia and knee joint diameter was measured on days 0, 7, 14, 21, 28, 35, 42, and 49. IL-1ß levels were measured on day 21 and day 49 after MIA injection. Results MIA injection successfully induced OA as marked by a significant difference in the time of latency to heat stimulus (p < 0.01) and a significant increase in joint diameter (p < 0.01). On day 21, IL-1ß levels showed a significant decrease in MIA injection (p = 0.05). The administration of meloxicam and glucosamine did not induce significant decrease in knee joint diameter (p > 0.10), but was able to significantly increase the latency time to heat stimulus (p < 0.01). IL-1ß levels also showed a significant decrease after administering a combination of glucosamine and meloxicam (p < 0.01). Conclusions Taken together, the use of glucosamine as an adjuvant in meloxicam therapy may be caused by the synergistic mechanism of meloxicam for the attenuation of OA development through systemically reducing IL-1ß.

Dopaminergic mechanisms in the lateral hypothalamus regulate feeding behavior in association with neuropeptides.

This study investigated dopaminergic function in the lateral hypothalamus (LH) in the regulation of feeding behavior. Refeeding increased dopamine levels in the LH. Glucose injection also increased dopamine levels in the LH. When the retrograde tracer Fluoro-Gold (FG) was injected into the LH, FG-positive cells were found in the ventral tegmental area (VTA) and the substantia nigra pars compacta (SNC), which were mostly tyrosine hydroxylase-positive. Injection of the dopamine D1 receptor agonist SKF 38393, but not the antagonist SCH 23390, into the LH increased food intake. Similarly, injection of the dopamine D2 receptor agonist quinpirole, but not the antagonist l-sulpiride, into the LH increased food intake. The effect of each agonist was blocked by its respective antagonist. Furthermore, injection of quinpirole, but not SKF 38393, decreased the mRNA level of preproorexin. In addition, injection of SKF 38393 decreased the mRNA levels of neuropeptide Y and agouti-related peptide, whereas the injection of quinpirole increased the mRNA level of proopiomelanocortin. These results indicate that food intake activates dopamine neurons projecting from the VTA/SNC to the LH through an increase in blood glucose levels, which terminates food intake by stimulation of dopamine D1 and D2 receptors. It is also possible that stimulation of dopamine D1 and D2 receptors in the LH inhibits feeding behavior through different neuropeptides.

Pregabalin increases food intake through dopaminergic systems in the hypothalamus.

Pregabalin is useful for treating neuropathic pain, but known to increase body weight as a side effect. To investigate the mechanism of this increase in body weight, we focused on dopamine in the lateral hypothalamus (LH) and examined the effects of pregabalin on dopamine levels in the LH and food intake. The dopamine levels in the LH was gradually decreased during fasting. When the animals were fed, dopamine levels in the LH was significantly increased, indicating that dopamine levels in the LH reflects energy state. The systemic injection of pregabalin tended to decrease dopamine levels in the LH after feeding. The dopamine levels in the LH was also significantly increased by glucose injection, which was inhibited by pregabalin. These results suggest that pregabalin inhibits dopaminergic function in the LH, which might increase food intake. To make these points clear, we examined the effects of pregabalin on food intake and blood glucose levels. Pregabalin significantly increased food intake, whereas pregabalin did not affect blood glucose levels. These results indicate that pregabalin stimulates feeding behavior, but not glucose metabolism. Moreover, the non-selective dopamine receptor antagonist cis-(Z)-flupenthixol injected into the LH significantly increased food intake, though neither the dopamine D1 receptor antagonist SCH 23390 nor the D2 receptor antagonist l-sulpiride injected into the LH affected food intake. These results indicate that the inhibition of dopaminergic function in the LH increases food intake. In conclusion, the present results suggest that pregabalin increases food intake through the inhibition of dopaminergic functions in the LH.