Multifunctional Derivatives of Spiropyrrolidine Tethered Indeno-Quinoxaline Heterocyclic Hybrids as Potent Antimicrobial, Antioxidant and Antidiabetic Agents: Design, Synthesis, In Vitro and In Silico Approaches.

To combat emerging antimicrobial-resistant microbes, there is an urgent need to develop new antimicrobials with better therapeutic profiles. For this, a series of 13 new spiropyrrolidine derivatives were designed, synthesized, characterized and evaluated for their in vitro antimicrobial, antioxidant and antidiabetic potential. Antimicrobial results revealed that the designed compounds displayed good activity against clinical isolated strains, with 5d being the most potent (MIC 3.95 mM against Staphylococcus aureus ATCC 25923) compared to tetracycline (MIC 576.01 mM). The antioxidant activity was assessed by trapping DPPH, ABTS and FRAP assays. The results suggest remarkable antioxidant potential of all synthesized compounds, particularly 5c, exhibiting the strongest activity with IC50 of 3.26 ± 0.32 mM (DPPH), 7.03 ± 0.07 mM (ABTS) and 3.69 ± 0.72 mM (FRAP). Tested for their α-amylase inhibitory effect, the examined analogues display a variable degree of α-amylase activity with IC50 ranging between 0.55 ± 0.38 mM and 2.19 ± 0.23 mM compared to acarbose (IC50 1.19 ± 0.02 mM), with the most active compounds being 5d, followed by 5c and 5j, affording IC50 of 0.55 ± 0.38 mM, 0.92 ± 0.10 mM, and 0.95 ± 0.14 mM, respectively. Preliminary structure-activity relationships revealed the importance of such substituents in enhancing the activity. Furthermore, the ADME screening test was applied to optimize the physicochemical properties and determine their drug-like characteristics. Binding interactions and stability between ligands and active residues of the investigated enzymes were confirmed through molecular docking and dynamic simulation study. These findings provided guidance for further developing leading new spiropyrrolidine scaffolds with improved dual antimicrobial and antidiabetic activities.

Gas chromatography-mass spectrometry (GM-MS) analysis and biological activities of the aerial part of Cleome amblyocarpa Barr. and Murb.

Cleome amblyocarpa Barr. and Murb is a medicinal plant widespread in North Africa and widely used in Tunisia to treat diabetes and colic. The non-volatile (polyphenols, flavonoids, tannins, and flavonols) and volatile compounds (GC-MS) of C. amblyocarpa leaves and stems have been studied. The antioxidant, antimicrobial, analgesic, and cytotoxic activities of hydroalcoholic extracts of C. amblyocarpa leaves and stems were also investigated. The major volatile components were ß-caryophyllene (46.9%), eugenol (25.6%), ethyl 3-methylpentanoate (16.2%), 7-epi-silphiperfol-5-ene (11.0%), and α-copaene (7.0%). The antioxidant activity has been evaluated using various in vitro assays, such as DPPH free radical scavenging activity, iron-chelating capability, and ability to inhibit lipid peroxidation (TBARS). The antibacterial and antifungal effectiveness of leaves and stems parts of Cleome amblyocarpa were investigated by means of the disc diffusion and microdilution techniques. The in vitro cytotoxicity of the hydroalcoholic extract of C. amblyocarpa on A549 and H1299 lung adenocarcinoma cells was determined using the crystal violet assay. The acute toxicity of the extracts on Swiss albino mice at the doses of 3000, 1500, and 500 mg/kg body weight was evaluated. The analgesic effect of leaves and stems extract was also determined by means of the acetic acid induced writhing test. The results indicated that the leaves have higher phenols, and flavonoids contents and potential antioxidant, antimicrobial, and anticancer activities in comparison to stem. In addition, the aerial part of C. amblyocarpa did not cause signs of toxicity or death in animals at doses up to 3000 mg/kg and have a significant analgesic activity.

Antiproliferative and apoptosis-inducing effect of common Tunisian date seed (var. Korkobbi and Arechti) phytochemical-rich methanolic extract.

In this study, the potential of date seed extracts to induce growth inhibition and apoptosis in HepG2 and HeLa cells was investigated. Analysis of the phytochemical compound content of the two Tunisian minor date seed extracts named Arechti and Korkobbi was determined. Moreover, their antioxidant properties are assessed through different assays including DPPH, ABTS, FRAP, TBARS, and phosphomolybdenum methods. Whereas, the cytotoxic effect was evaluated and apoptosis induction was confirmed by western blot technique (caspase-9, caspase-3, and PARP-1). The results proved the richness in phytochemical compounds of these by-products which explains the high in vitro antioxidant activity and the antiproliferative effects of both seed extracts. Additionally, the decrease in total PARP-1, procaspase-3 levels, and the increase of cleaved caspase-9 revealed the apoptotic effect of date seed extracts. These results collectively illustrate the potential of date seed extracts to induce growth inhibition and apoptosis in HepG2 and HeLa cells thanks to its phytochemical richness.

Effect of solvents extraction on phytochemical components and biological activities of Tunisian date seeds (var. Korkobbi and Arechti).

BACKGROUND: The interest in natural antioxidants, especially polyphenols, is growing more and more thanks to their positive contribution to human health. Thus, the prevention from the harmful action of oxidative stress which has been involved in many diseases such as cancer, inflammation diabetes, and cardiovascular illness. Recent research proved the bioactive compounds richness of date seeds which could be a good biological matrix of natural antioxidants. Unfortunately, an important quantity of Tunisian dates seed is discarded yearly. METHODS: In this study, different solvents extraction (water, methanol, absolute acetone and aqueous acetone 80%) were used and the evaluation of its effect on phytochemical level, in vitro antioxidant activities, in vitro hyperglycemia key enzymes inhibition and in vivo anti-inflammatory proprieties were established for Tunisian date seeds. RESULTS: The result revealed that the polar solvent exhibited the highest amount of bioactive compounds. The correlation between polyphenol compounds and the antioxidant potentiality explains the powerful effect of used polar solvents on inflammation, TBARS and hyperglycemia inhibition. Furthermore, it showed its higher capacity to scavenge radicals. CONCLUSIONS: Therefore, this big waste of Tunisian seeds could be used as cheap source of natural antioxidant compounds which are considered as a health challenge for the poor countries.

Dichloroacetic acid-induced testicular toxicity in male rats and the protective effect of date fruit extract.

BACKGROUND: The present study was designed to investigate the protective effect of aqueous date extract (ADE) against the dichloroacetic acid (DCA)-induced testicular injury in rats. METHODS: Forty-eight male Wistar rats were randomly divided into six groups of eight: group I served as the control; group II was given ADE (4 ml/kg) by gavage; groups III and IV received DCA at 0.5 and 2 g/L drinking water, respectively; and groups V and VI received DCA at 0.5 and 2 g/L drinking water, respectively, before ADE administration. The experiment was performed for two months. RESULTS: Results showed that the absolute weights of testes and epididymis were decreased following the DCA administration. The testosterone, FSH and LH levels were also decreased. Severe histopathological changes in testes were observed including degeneration of seminiferous tubules and depletion of germ cells. These changes were associated with alterations of oxidative stress markers. Levels of lipid peroxidation and SOD and CAT activities were increased, while activity of GPx and GSH levels were decreased. Pretreatment with ADE has effectively alleviated the oxidative stress induced by DCA thereby restoring these parameters to normal values. CONCLUSIONS: These results suggest that ADE has a protective effect over DCA-induced oxidative damage in rat testes.

Oxidative damage and alterations in antioxidant enzyme activities in the kidneys of rat exposed to trichloroacetic acid: protective role of date palm fruit

In this study, we investigated the antioxidant and protective properties of date fruit aqueous extract (DFAE) on trichloroacetic acid (TCA)-induced nephrotoxicity in rat. Oral administration of TCA as drinking water (0.5 and 2 g/L) daily for 2 months caused nephrotoxicity as evident by elevated levels of plasma creatinine, urea, and uric acid. Activity of antioxidant enzymes, catalase (CAT) and glutathione peroxidase (GPx), was decreased, whereas superoxide dismutase (SOD) activity and malondialdehyde (MDA) level were increased along with histopathological injuries. The oral administration of DFAE (4 mL/kg/day) to TCA-treated groups proved some significant correction by increasing the antioxidant activity of the CAT and GPx enzymes and normalizing the SOD activity and the MDA level (p < 0.05). It also protected kidney's histology and normalized the functions of this organ. It could be concluded that DFAE has a protective role against TCA-induced oxidative stress in rat, thereby protecting the renal tissue from TCA-induced damage

Aqueous date fruit extract protects against lipid peroxidation and improves antioxidant status in the liver of rats subchronically exposed to trichloroacetic acid

Trichloroacetic acid (TCA) is a prominent by-product of the chlorination of drinking water. It induces cell damage by producing free radicals and reactive oxygen species. The present study was carried out to evaluate the potential hepatoprotective role of the aqueous date extract (ADE) against TCA-induced liver injury. Forty-eight male Wistar rats were randomly divided into six groups of eight: group I served as the control; group II was given ADE by gavage; groups III and IV received TCA as drinking water at 0.5 and 2 g/L, respectively; and groups V and VI were treated with ADE by gavage and then received TCA at 0.5 and 2 g/L, respectively, as drinking water. The experiment was performed for 2 months. The hepatotoxicity of TCA administration was revealed by an increase in the levels of hepatic marker enzymes (transaminases, gamma-glutamyl transferase, and lactate dehydrogenase) and conjugated bilirubin and a decrease in albumin level. The TCA administration induced also significant elevation of the malondialdehyde (MDA) level and the antioxidant activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) paralleled with a significant decline in catalase (CAT) activity. These biochemical alterations were accompanied by histological changes marked by the appearance of vacuolization, necrosis, congestion, inflammation, and enlargement of sinusoids in the liver section. Treatment with date palm fruit extract restored the liver damage induced by TCA, as demonstrated by inhibition of hepatic lipid peroxidation; amelioration of SOD, GPx, and CAT activities; and improvement of histopathology changes. These results suggest that ADE has a protective effect over TCA-induced oxidative damage in rat liver

Aqueous date fruit extract protects against lipid peroxidation and improves antioxidant status in the liver of rats subchronically exposed to trichloroacetic acid.

Trichloroacetic acid (TCA) is a prominent by-product of the chlorination of drinking water. It induces cell damage by producing free radicals and reactive oxygen species. The present study was carried out to evaluate the potential hepatoprotective role of the aqueous date extract (ADE) against TCA-induced liver injury. Forty-eight male Wistar rats were randomly divided into six groups of eight: group I served as the control; group II was given ADE by gavage; groups III and IV received TCA as drinking water at 0.5 and 2 g/L, respectively; and groups V and VI were treated with ADE by gavage and then received TCA at 0.5 and 2 g/L, respectively, as drinking water. The experiment was performed for 2 months. The hepatotoxicity of TCA administration was revealed by an increase in the levels of hepatic marker enzymes (transaminases, gamma-glutamyl transferase, and lactate dehydrogenase) and conjugated bilirubin and a decrease in albumin level. The TCA administration induced also significant elevation of the malondialdehyde (MDA) level and the antioxidant activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) paralleled with a significant decline in catalase (CAT) activity. These biochemical alterations were accompanied by histological changes marked by the appearance of vacuolization, necrosis, congestion, inflammation, and enlargement of sinusoids in the liver section. Treatment with date palm fruit extract restored the liver damage induced by TCA, as demonstrated by inhibition of hepatic lipid peroxidation; amelioration of SOD, GPx, and CAT activities; and improvement of histopathology changes. These results suggest that ADE has a protective effect over TCA-induced oxidative damage in rat liver.

Nephroprotective effect of date fruit extract against dichloroacetic acid exposure in adult rats.

The aim of this study was to investigate the protective effects of aqueous date extract (ADE) on dichloroacetic acid (DCA)-induced nephrotoxicity. In vitro, total phenolic content estimated in the ADE were 417.71mg gallic acid equivalents/100g fresh weights (FW), while total flavonoid and tannins contents were 285.23 and 73.65mg catechin equivalents/100g FW, respectively. The ADE has strong scavenging activity. Ferulic, caffeic and p-coumaric acids are the major's compounds. Nephrotoxicity was induced in male Wistar rats by the administration of 0.5 and 2g/L DCA as drinking water. Some of these rats received also by gavage ADE (4mL/kg) before the administration of DCA. After two months of experiment, DCA administration caused elevated levels of renal MDA, significant depletion of GSH levels, altered the antioxidant enzyme activities and deteriorated the renal functions as assessed by the increased plasma urea, uric acid and creatinine levels compared to control rats. The treatment with the ADE significantly normalized the increased plasma levels of creatinine, urea and uric acid, reduced the elevated MDA levels, significantly normalized the antioxidant enzyme activities and GSH level and restored the altered kidney histology in rats treated with DCA. Therefore, it was speculated that ADE protects rats from kidney damage through its antioxidant capacity.

Oxidative damage and alterations in antioxidant enzyme activities in the kidneys of rat exposed to trichloroacetic acid: protective role of date palm fruit.

In this study, we investigated the antioxidant and protective properties of date fruit aqueous extract (DFAE) on trichloroacetic acid (TCA)-induced nephrotoxicity in rat. Oral administration of TCA as drinking water (0.5 and 2 g/L) daily for 2 months caused nephrotoxicity as evident by elevated levels of plasma creatinine, urea, and uric acid. Activity of antioxidant enzymes, catalase (CAT) and glutathione peroxidase (GPx), was decreased, whereas superoxide dismutase (SOD) activity and malondialdehyde (MDA) level were increased along with histopathological injuries. The oral administration of DFAE (4 mL/kg/day) to TCA-treated groups proved some significant correction by increasing the antioxidant activity of the CAT and GPx enzymes and normalizing the SOD activity and the MDA level (p < 0.05). It also protected kidney's histology and normalized the functions of this organ. It could be concluded that DFAE has a protective role against TCA-induced oxidative stress in rat, thereby protecting the renal tissue from TCA-induced damage.