In vivo sedative and muscle relaxants activity of Diospyros lotus L

In-vitro antioxidant, lipoxygenase inhibitory, and in-vivo muscle relaxant potential of the extract and constituent isolated from Diospyros kaki (Japanese Persimmon)

Diospyros kaki (Japanese persimmon) is cultivated specious of the Diospyros genus. D. kaki is a multi-medicinal application in the folk system for the cure of ischemic stroke, angina, atherosclerosis, muscle relaxation, internal hemorrhage, hypertension, high cough, and infectious disease. The main objective of this study was the isolated bioactive metabolites from chloroform fractions of D. kaki. The extract and fractions were then tested for various in-vitro (antioxidant and lipoxygenase) and in-vivo (muscle relaxant) activities. The repeated chromatographic separation of chloroform extract afforded compound 1. Compound 1, n-hexane, and chloroform fractions were evaluated for in vitro antioxidant, lipoxygenase inhibitory, and in vivo muscle relaxant potency. The chloroform extract has 79.54% interaction with DPPH at higher concentrations (100 μg/ml) while the compound exhibited a maximum effect of 95.09% at 100 μg/ml. Compound 1 exhibited significant lipoxygenase inhibitory activity with an IC₅₀ value of 36.98 μM followed by a chloroform extract of 57.09 μM. Similarly, compound 1 and chloroform extract showed excellent muscle relaxant effects at a higher dose. From this investigation, it is concluded that extracts and pure compounds exhibited promising antioxidant, lipoxygenase inhibitory, and muscle relaxant activity. This study excellently rationalizes the traditional usage of D. kaki in curing various diseases. Furthermore, the docking results indicate, that the isolated compound fits well into the active site of the lipoxygenase, and makes strong interactions with the target protein.

Formulation of tizanidine hydrochloride-loaded provesicular system for improved oral delivery and therapeutic activity employing a 23 full factorial design

Tizanidine hydrochloride (TZN) is one of the most effective centrally acting skeletal muscle relaxants. The objective of this study is to prepare TZN-loaded proniosomes (TZN-PN) aiming at enhanced oral delivery and therapeutic activity. TZN-PN were prepared by coacervation phase separation method. The developed vesicles were characterized via entrapment efficiency percentage (EE%), vesicular size (VS), and zeta potential (ZP). A 2³ full factorial design was employed to attain an optimized TZN-PN formulation. The optimized TZN-PN were further characterized via in vitro release study and transmission electron microscopy (TEM). In vivo rotarod test was employed for determination of the muscle relaxant activities of rats and levels of GABA and EAAT2 were detected. The developed TZN-PN exhibited relatively high EE% (75.78-85.45%), a VS ranging between (348-559 nm), and a ZP (-26.47 to -59.64). In vitro release profiles revealed sustained release of TZN from the optimized TZN-PN, compared to free drug up to 24 h. In vivo rotarod study revealed that the elevation in coordination was in the following order: normal control < free TZN < market product < TZN-PN (F6). Moreover, the optimized TZN-PN exhibited significant elevated coordination activity by 39% and 26% compared to control group and market product group, respectively. This was accompanied with an elevation in both GABA and EAAT2 serum levels. Thus, it could be concluded that encapsulation of TZN in the provesicular nanosystem proniosomes has enhanced the anti-nociceptive effect of the drug and consequently its therapeutic activity.

Sedative-hypnotic effect and in silico study of dinaphthodiospyrols isolated from Diospyros lotus Linn

Traditionally, Diospyros lotus Linn is used for insomnia and other associated disorders. Insomnia is a worldwide disorder with different etiology which is treated with different synthetic medicine associated with addiction. Natural products are generally devoid of such addition with good efficacy. Current research was conducted to evaluate the sedative and hypnotic effects of dimeric naphthoquinones such as dinaphthodiospyrol A (1), dinaphthodiospyrol B (2), dinaphthodiospyrol C (3), dinaphthodiospyrol D (4), dinaphthodiospyrol E (5) and dinaphthodiospyrol F (6) isolated from the chloroform fractions of D. lotus. The sedative and hypnotic effects at the dose of 5 and 10 mg/kg (each compound) were assessed through open field and phenobarbital induced sleep test, respectively. In the case of open field test the administration of tested compounds significantly hindered the movement of animals, while in case of hypnotic effect the tested samples significantly improved the onset and duration of sleep as compared to control. The overall effects were in a dose dependent manner. The compounds were also assessed for acute toxicity, but no toxicity was observed. In this regard, our research triumphantly announced the strong chemical base for the folkloric values of the plant with their fringe benefits and implemented a platform for further aspects of mechanistic and clinical studies. A possible mechanism of in vivo inhibition was studied by using docking simulations on GABA receptors. Binding orientations and types of interactions revealed that a possible mechanism behind these pharmacological actions might be interaction with GABA receptors.

Protective effect of fermented Diospyros lotus L. extracts against the high glucose-induced apoptosis of MIN6 cells

Date plum persimmon (Diospyros lotus L.) is a fruit crop from the Ebenaceae family. Its microorganism-fermented extract (DPEML) was shown to exhibit a hypoglycemic effect in our previous work. Here, we investigated the effects of DPEML fermented by Microbacterium flavum YM18-098 and Lactobacillus plantarum B7 on the high glucose-induced apoptosis of MIN6 cells and explored its potential cell protective mechanisms. DPEML ameliorated the apoptosis of MIN6 cells cultured under high glucose conditions, thereby improving cell viability. DPEML upregulated the Bcl-2/Bax mRNA ratio to obstruct an intrinsic apoptotic pathway and concomitantly downregulated the expression of the apoptosis-linked proteins, AIF, and Cyt-C, in high glucose-induced MIN6 cells. Furthermore, DPEML promoted the insulin secretion of MIN6 cells grown under chronically high-glucose conditions by upregulating Ins mRNA expression. In summary, our study suggested that DPEML is a promising functional food for the development of therapeutics for the treatment of Type 2 diabetes mellitus. PRACTICAL APPLICATIONS: We investigated the effects of DPEML fermented by Microbacterium flavum YM18-098 and Lactobacillus plantarum B7 on the high glucose-induced apoptosis of MIN6 cells and explored its potential cell protective mechanisms. DPEML ameliorated the apoptosis of MIN6 cells cultured under high glucose conditions, thereby improving cell viability. DPEML upregulated the Bcl-2/Bax mRNA ratio to obstruct an intrinsic apoptotic pathway and concomitantly downregulated the expression of the apoptosis-linked proteins, AIF and Cyt-C, in high glucose-induced MIN6 cells. Furthermore, DPEML promoted the insulin secretion of MIN6 cells grown under chronically high-glucose conditions by upregulating Ins mRNA expression. We suggested that DPEML is a promising functional food for the development of therapeutics for the treatment of Type 2 diabetes mellitus.

Antibacterial, Antifungal, Antioxidant, and Docking Studies of Potential Dinaphthodiospyrols from Diospyros lotus Linn Roots

The main aims of this investigation were the isolation of dimeric naphthoquinones, a new class of dinaphthodiospyrols (1-7), from chloroform fractions and screening them for antibacterial, antifungal, and antioxidant potential. The susceptibility of the isolated compounds, namely, dinaphthodiospyrol A (1), dinaphthodiospyrol B (2), dinaphthodiospyrol C (3), dinaphthodiospyrol D (4), dinaphthodiospyrol E (5), dinaphthodiospyrol F (6), and dinaphthodiospyrol G (7) was assessed for antibacterial potential using well diffusion methods. The isolated compounds showed excellent antibacterial activity against selected bacterial strains, including Gram-positive Bacillus subtilis, Streptococcus epidermis, and Bacillus subtilis, and Gram-negative bacteria Klebsiella pneumonia with the zones of inhibition 6 to 26 nm. The standard drug Imipenem showed a maximum inhibitory zone 30 to 35 nm. Similarly, the isolated compounds were screened for antifungal properties, which showed an excellent reduction in the growth of selected fungal strain including Candida albicans, Aspergillus flavus, Fusarium solani, Trichyton logifusus, Microsporum canis , and Candida glabrata. Among all the screened compounds, 7 exhibited good activity (30-49 mm), followed by compounds 5 and 6, (35-46 mm), while compounds 1-4 showed a moderate effect (8-28 mm) against the selected fungal strain against miconazole which showed potent effects (101-110.98 mm). The isolated compounds were also screened for 1, 1-diphenyl-2-picrylhydrazyl (DPPH) activity. In vitro-based free radical was employed using ascorbic acid as a standard antioxidant. The tested compounds (1-7) exhibited significant antioxidant activity in a concentration-dependent manner. The dinaphthodiospyrol 7 exhibited 97.32% scavenging activity, followed by dinaphthodiospyrol 6, 92.01%, and compounds 5 and 4 with 89.90 and 88.43% scavenging activity at 100 μg/mL, respectively; ascorbic acid showed 96.45% scavenging effect. Furthermore, docking analysis was performed to know the exact binding mode of the tetra-substituted derivatives of dinaphthodiospyrols to the selected target proteins. From the docking analysis, it was found that the docking results are well correlated with the experimental observations. In conclusion, the dinaphthodiospyrols exhibited excellent antibacterial, antifungal, and free radical scavenging potential.

In vivo analgesic, anti-inflammatory, and sedative activity and a molecular docking study of dinaphthodiospyrol G isolated from Diospyros lotus

BACKGROUND

Analgesic, anti-inflammatory, and sedative drugs are available with potential side effects such as peptic ulcer and addiction among other things. In this regard, research is underway to find safe, effective, and economical drugs free of these side effects. In this study, an isolated natural product from Diospyros lotus, was tested for the aforementioned bioactivities.

OBJECTIVES

To evaluate analgesic, anti-inflammatory, and sedative potential of D. lotus extracts in animal paradigms using BALB/c mice as experimental model.

METHODS

Analgesic, anti-inflammatory and sedative activities of dinaphthodiospyrol G (1) isolated from the chloroform fraction of D. lotus were evaluated using different experimental procedures. Anti-inflammatory effect was evaluated using the carrageenan and histamine-induced paw edema, whereas the antinociceptive effect was quantified by means of the hot plate analgesiometer. On the other hand, the sedative effect was determined using animal assay for screening the locomotors effects of compound 1. Compound 1 was also subjected to molecular modeling studies against cyclooxygenase enzymes.

RESULTS

Results from this investigation showed that the extract is devoid of anti-inflammatory and antinociceptive potentials but has a significant sedative effect, whereas the tested compound exhibited 55.23 and 78.34% attenuation in paw edema by carrageenan and histamine assays, respectively. A significant (p < 0.001) and dose-dependent antinociceptive and sedative effects were demonstrated by the isolated compound. Molecular docking and dynamics simulation studies of the isolated compound against cyclooxygenase enzyme indicated that compound 1 forms specific interactions with key residues in the active site of the target receptor, which validates the potential use of the isolated compound as cyclooxygenase inhibitor.

CONCLUSIONS

Compound 1 exhibited remarkable analgesic, anti-inflammatory, and sedative activities. These findings strongly justify the traditional use of D. lotus in the treatment of inflammation, pain, and insomnia.

Anti-inflammatory, Antibacterial, Toxicological Profile, and In Silico Studies of Dimeric Naphthoquinones from Diospyros lotus

Diospyros lotus, also known as date-plum, belongs to the Ebenaceae family and is mostly recognized as a rootstock for D. kaki. Similar classes of naphthoquinones in D. lotus are investigated against cancer and inflammation and have antimicrobial, sedative, and analgesic properties. Six chemical constituents (1-6) were isolated from Diospyros lotus and tested for anti-inflammatory effects at the dose of 2.5 and 5 mg/kg, i.p., using carrageenan (1%, 0.05 ml)-induced paw edema. The maximum protection against carrageenan-induced edema was observed for compounds 1 and 2. Both studied compounds demonstrated significant anti-inflammatory effect after the 3rd hour of posttreatment. The maximum anti-inflammatory effect of compound 1 was 85.96%, while that of compound 2 was 81.44%, followed by compounds 5 and 6, which exhibited 80.11% and 82.45% effect, respectively. Similarly, histamine-induced inflammation was significantly antagonized by 1, 2, 5, and 6 with 87.99%, 82.18±1.8, 80.40±1.59, and 77.44% effects, respectively, at 5 mg/kg after the 2nd hour of posttreatment. The rest of the tested compounds did not show any significant effect as compared to the negative control. Interestingly, no toxicity was observed at higher doses. Moreover, the extracted compounds showed remarkable antibacterial activity against the Gram-positive bacteria and no effect against the Gram-negative bacteria. Docking studies on target cyclooxygenases showed that all the compounds established interactions with the key amino acid residues present in the additional pocket of COX-2. Hence, these compounds may act as selective COX-2 inhibitors. In conclusion, the findings of the current study suggest that the roots of Diospyros lotus may contain some anti-inflammatory and antibacterial agents with minimal toxicological effects and accordingly this plant product is recommended for further investigations.

Diospyros, an under-utilized, multi-purpose plant genus: A review

The genus Diospyros from family Ebenaceae has versatile uses including edible fruits, valuable timber, and ornamental uses. The plant parts of numerous species have been in use as remedies in various folk healing practices, which include therapy for hemorrhage, incontinence, insomnia, hiccough, diarrhea etc. Phytochemical constituents such as terpenoids, ursanes, lupanes, polyphenols, tannins, hydrocarbons, and lipids, benzopyrones, naphthoquinones, oleananes, and taraxeranes have been isolated from different species of this genus. The biological activities of these plants such as antioxidant, anti-inflammatory, analgesic, antipyretic, anti-diabetic, antibacterial, anthelmintic, antihypertensive, cosmeceutical, enzyme-inhibitory etc. have been validated by means of an in vitro, in vivo, and clinical tests. As a rich reserve of pharmacologically important components, this genus can accelerate the pace of drug discovery. Accordingly, the aim of the present review is to survey and summarize the recent literature pertaining to the medicinal and pharmacological uses of Diospyros, and to select experimental evidence on the pharmacological properties of this genus. In addition, the review also aims at identifying areas that need development to make use of this genus, especially its fruit and phytochemicals as means for economic development and for drug discovery.