Histochemical, metabolic and ultrastructural changes in leaf patelliform nectaries explain extrafloral nectar synthesis and secretion in Clerodendrum chinense.

BACKGROUND AND AIMS: Extrafloral nectaries are nectar-secreting structures present on vegetative parts of plants which provide indirect defences against herbivore attack. Extrafloral nectaries in Clerodendrum chinense are patelliform-shaped specialized trichomatous structures. However, a complete understanding of patelliform extrafloral nectaries in general, and of C. chinense in particular, has not yet been established to provide fundamental insight into the cellular physiological machinery involved in nectar biosynthesis and secretory processes. METHODS: We studied temporal changes in the morphological, anatomical and ultrastructural features in the architectures of extrafloral nectaries. We also compared metabolite profiles of extrafloral nectar, nectary tissue, non-nectary tissue and phloem sap. Further, both in situ histolocalization and normal in vitro activities of enzymes related to sugar metabolism were examined. KEY RESULTS: Four distinct tissue regions in the nectar gland were revealed from histochemical characterization, among which the middle nectariferous tissue was found to be the metabolically active region, while the intermediate layer was found to be lipid-rich. Ultrastructural study showed the presence of a large number of mitochondria along with starch-bearing chloroplasts in the nectariferous region. However, starch depletion was noted with progressive maturation of nectaries. Metabolite analysis revealed compositional differences among nectar, phloem sap, nectary and non-nectary tissue. Invertase activity was higher in secretory stages and localized in nectariferous tissue and adjacent region. CONCLUSIONS: Our study suggests extrafloral nectar secretion in C. chinense to be both eccrine and merocrine in nature. A distinct intermediate lipid-rich layer that separates the epidermis from nectary parenchyma was revealed, which possibly acts as a barrier to water flow in nectar. This study also revealed a distinction between nectar and phloem sap, and starch could act as a nectar precursor, as evidenced from enzymatic and ultrastructural studies. Thus, our findings on changing architecture of extrafloral nectaries with temporal secretion revealed a cell physiological process involved in nectar biosynthesis and secretion.

Molecular Insight into the Pharmacological Potential of Clerodendrum minahassae Leaf Extract for Type-2 Diabetes Management Using the Network Pharmacology Approach.

Background and Objectives: The increasing occurrence and prevalence of type-2 diabetes mellitus (T2DM) have led to a growing interest in researching available treatment alternatives. Clerodendrum minahassae, a native plant species of North Sulawesi, has been a focus of ethnopharmacological studies due to its significance contributions to drug development, particularly its potential antidiabetic properties. This study investigated the pharmacological potential of Clerodendrum minahassae (CM) leaf extract for managing type-2 diabetes (T2DM) using a network pharmacology approach. Materials and Methods: Active compounds were extracted from CM leaves, and their interactions with target proteins in T2DM were explored through various in silico analyses. Results: SAR analysis using Way2Drug Pass Online identified 29 bioactive CM leaf extract compounds with promise as T2DM treatments. Additionally, 26 of these met Ro5 criteria for favorable drug-likeness. Most compounds exhibited positive pharmacodynamic and pharmacokinetic profiles, with 22 considered safe, while 7 posed potential toxicity risks when ingested individually. CM leaf extract targeted 60 T2DM-related proteins, potentially affecting T2DM via cytokine regulation, particularly in proteins linked to metabolic processes, cellular response to angiotensin, and the sphingosine-1-phosphate signaling pathway. The network pharmacology analysis identified five genes targeted by CM leaf extract, namely, STAT3, MAPK1, ESR1, PIK3R1, and NFKB1. Among these genes, PIK3R1's interaction with the insulin receptor (INSR) positions it as a crucial candidate gene due to its pivotal role in insulin signal transduction during T2DM development. Conclusions: This research sheds light on the therapeutic potential of CM leaf extract for treating T2DM. This potential is attributed to the diverse array of bioactive compounds present in the extract, which have the capacity to interact with and inhibit proteins participating in the insulin signal transduction pathway crucial for the progression of T2DM. The findings of this study may open up possibilities for future applications of CM leaf extract in the development of novel T2DM treatments.

Hesperetin from Root Extract of Clerodendrum petasites S. Moore Inhibits SARS-CoV-2 Spike Protein S1 Subunit-Induced NLRP3 Inflammasome in A549 Lung Cells via Modulation of the Akt/MAPK/AP-1 Pathway.

Inhibition of inflammatory responses from the spike glycoprotein of SARS-CoV-2 (Spike) by targeting NLRP3 inflammasome has recently been developed as an alternative form of supportive therapy besides the traditional anti-viral approaches. Clerodendrum petasites S. Moore (C. petasites) is a Thai traditional medicinal plant possessing antipyretic and anti-inflammatory activities. In this study, C. petasites ethanolic root extract (CpEE) underwent solvent-partitioned extraction to obtain the ethyl acetate fraction of C. petasites (CpEA). Subsequently, C. petasites extracts were determined for the flavonoid contents and anti-inflammatory properties against spike induction in the A549 lung cells. According to the HPLC results, CpEA significantly contained higher amounts of hesperidin and hesperetin flavonoids than CpEE (p < 0.05). A549 cells were then pre-treated with either C. petasites extracts or its active flavonoids and were primed with 100 ng/mL of spike S1 subunit (Spike S1) and determined for the anti-inflammatory properties. The results indicate that CpEA (compared with CpEE) and hesperetin (compared with hesperidin) exhibited greater anti-inflammatory properties upon Spike S1 induction through a significant reduction in IL-6, IL-1ß, and IL-18 cytokine releases in A549 cells culture supernatant (p < 0.05). Additionally, CpEA and hesperetin significantly inhibited the Spike S1-induced inflammatory gene expressions (NLRP3, IL-1ß, and IL-18, p < 0.05). Mechanistically, CpEA and hesperetin attenuated inflammasome machinery protein expressions (NLRP3, ASC, and Caspase-1), as well as inactivated the Akt/MAPK/AP-1 pathway. Overall, our findings could provide scientific-based evidence to support the use of C. petasites and hesperetin in the development of supportive therapies for the prevention of COVID-19-related chronic inflammation.

Probable mechanisms involved in the antiepileptic activity of Clerodendrum polycephalum Baker (Labiatae) leaf extract in mice exposed to chemical-induced seizures.

The leaves of Clerodendrum polycephalum Baker (Labiatae) are used as a dietary legume supplement and applied ethnomedicinally for the management of epilepsy, convulsion, and spasms. This study is aimed at evaluating the effects of Clerodendrum polycephalum (CP) leaf extract on chemical-induced seizures in mice and the possible mechanisms of action. Swiss albino mice were pretreated with CP (50, 100, or 500 mg/kg, p.o.) prior to intraperitoneal injection of picrotoxin (PTX) or pentylenetetrazole (PTZ). However, the most effective dose was used to elucidate the role of GABAergic and nitric oxide-cyclic guanosine monophosphate (NO-cGMP) signaling mechanisms in mice brains. Accordingly, we evaluated the preventive and reversal effects of CP on kainic acid (KA)-induced temporal lobe epilepsy (TLE), oxidative stress, and neuroinflammatory in mice. The pretreatment of mice with CP delayed the latencies to PTX and PTZ-induced seizures and decrement in the period of tonic-clonic attacks. Interestingly, CP (100 mg/kg) completely prevented PTZ-induced tonic-clonic seizures. Contrastingly, flumazenil (benzodiazepine receptor antagonist), NG -nitro-L-Arginine (L-NNA) (10 mg/kg., neuronal nitric oxide synthase inhibitor), and methylene blue (MB) (2 mg/kg, a soluble guanylyl cyclase inhibitor) but not L-arginine (150 mg/kg., nitric oxide precursor) reversed CP-induced anticonvulsant-like effect in PTZ model. Furthermore, KA-elicited TLE was prevented by CP treatment. CP also attenuated KA-induced oxidative stress, cyooxygenase-2 (COX-2), and nuclear factor kappa-B (NF-κB) elevated expressions in the hippocampus. The study revealed that the ethanolic leaf extract of CP produced anticonvulsant actions through enhancement of antioxidant defense, GABAergic, and NO-cGMP signaling pathways as well as attenuation of inflammatory processes. PRACTICAL APPLICATIONS: The leaves of Clerodendrum polycephalum Baker (Labiatae) are used as a dietary legume supplement and applied ethnomedicinally for the management of epilepsy, convulsion, and spasms. For this reason, we believe that supplementation of the Clerodendrum polycephalum leaf extract would prevent epileptic-related disorders in mice induced with epileptic conditions using kainic acid and other behavioral phenotypic models. Here, our findings clearly revealed that Clerodendrum polycephalum leaf extract protects against conditions of epileptic-related disorders and thus might be relevant as a dietary supplement in the prevention or delay of the onset of seizures and epileptic behavior.

Enhanced antimicrobial, antioxidant, in vivo antitumor and in vitro anticancer effects against breast cancer cell line by green synthesized un-doped SnO2 and Co-doped SnO2 nanoparticles from Clerodendrum inerme.

A novel approach was employed for the synthesis of un-doped tinoxide and Cobalt-doped tinoxide (Co-doped SnO2) nanoparticles (NAPs) by using aqueous extract of Clerodendrum inerme with the help of eco-friendly superficial solution combustion method. Synthesized NAPs were characterized by different spectroscopic techniques and results from XRD, TEM, SEM, EDX and UV-Vis examines confirmed the successful synthesis, crystalline nature and spherical structure of un-doped SnO2 and Co-doped SnO2 NAPs with the average grain size of 30 and 40 nm; and band gap energy of 3.68 and 2.76 eV respectively. Antimicrobial propensity of the synthesized NAPs was determined by agar well assay, SEM, TEM and confocal laser scanning microscopic analysis against various bacterial and fungal strains. Synthesized Co-doped SnO2 NAPs were unveiled the extraordinary antibacterial and antifungal activities against E. coli, B. subtilis, A. niger, A. flavus, and C. albicans with the zone of inhibitions of 30 ±â€¯0.08 mm and 26 ±â€¯0.06 mm, 17 ±â€¯0.04 mm, 23 ±â€¯0.08 mm and 26 ±â€¯0.06 respectively which were also evidenced from SEM, TEM and confocal laser scanning microscopy. In addition, green synthesized Co-doped SnO2 NAPs were demonstrated the substantial antioxidant activity by scavenging DPPH, significant in vitro anticancer and in vivo antitumor activity on breast carcinoma cells (MCF-7) and Ehrlich ascites tumor cell lines respectively than standard. The hemolytic activity disclosed low cytotoxicity of fabricated NAPs (0.89 ±â€¯0.05%) at 5 mg/mL, which was indicated their biocompatibility potential. Hence, the multi-purpose properties of synthesized NAPs presented in the current study can be further deliberated for pharmaceutical and nanomedicine applications.

Phytochemical investigation and in vitro antinociceptive activity of Clerodendrum indicum leaves.

The crude ethanolic extracts of Clerodendrum indicum Linn. leaves were investigated for possible antinociceptive activity using acetic acid induced writhing model in mice. Phytochemical analysis was also carried out according to the standard procedures to identify the presence of different phytoconstituents in the ethanolic extract of the plant leaves. The study results showed 38.91 and 55.24% inhibition of writhings in the tested mice when ethanolic extract of Clerodendrum indicum Linn. leaves at doses of 250 and 500 mg kg(-1) body weight was given intraperitoneally, respectively. The study results were also compared with antinociceptive activity of the standard drug, Diclofenac sodium (68.37% inhibition) used at 25 mg kg(-1) body weight. At the above doses, the crude ethanolic extract of the plant showed significant antinociceptive activity in dose dependent fashion in acetic acid-induced writhing model in mice. The inhibition of writhings was calculated in respective to control group and it was found that p-values (<0.0001) obtained in all cases were extremely statistically significant. However, the phytochemical analysis showed the presence of alkaloid, steroid, saponin, tannin, reducing sugar and gum. The results suggest that crude ethanolic extracts of Clerodendrum indicum leaves possess significant antinociceptive properties justifying its folkloric use as analgesics and further research is necessary to isolate the principle phytochemical constituent(s) responsible for this activity.

Micropropagation of Clerodendrum aculeatum through adventitious shoot induction and production of consistent amount of virus resistance inducing protein.

Rapid micropropagation through adventitious shoot induction from in vitro raised leaf explants of Clerodendrum aculeatum (Verbenaceae), was successfully achieved for the first time. Basal portion of the leaves showed highest regeneration potential when grown on MS medium supplemented with BA (5.0 mg/l) and NAA and IBA (0.5 mg/l of each). Shoots after elongation in growth regulator-free medium, were rooted in MS medium containing 0.5 mg/l of NAA and IBA. Aqueous leaf extract of in vitro raised plants, induced high degree of resistance against viruses in susceptible healthy hosts when applied prior to virus inoculation. Upon purification from leaves of cultured plants, the resistance inducing protein, showed molecular mass of 34 kDa. Amount of resistance inducing protein obtained from leaves of cultured plants, was consistent throughout the year, as compared to the protein isolated from leaves of field grown plants, which showed marked seasonal fluctuation. The purified 34 kDa protein from in vitro raised plants, was serologically related to field grown plants and possessed similar characteristics. The micropropagated plants were successfully established in earthen pots under greenhouse conditions.