Effect of the metanolic extract from the leaves of Garcinia humilis Vahl (Clusiaceae) on acute inflammation

Tagetes erecta L.: A traditional medicine effective in inflammatory process treatment

ETHNOPHARMACOLOGICAL RELEVANCE

Tagetes erecta L. (Asteraceae), popularly known as Aztec Marigold, is used in folk medicine to treat several ailments including inflammatory processes. Despite its historical use, the specific mechanisms through which it may modulate inflammation, particularly its effects on neutrophils and macrophages activation, have not yet been completely investigated.

AIM OF THE STUDY

This study aimed to elucidate the anti-inflammatory mechanism of the hydroalcoholic extract obtained from T. erecta flowers, focusing on its role in the regulation of neutrophil and macrophage functions.

MATERIAL AND METHODS

The production of TNF, IL-6, CXCL-1, IL-1β, IL-10 (ELISA) and NO (Griess reaction), adhesion molecule expression (CD62L, CD49d and CD18, flow cytometry), and chemotaxis were analyzed in vitro using oyster glycogen-recruited peritoneal neutrophils or macrophages (RAW 264.7) stimulated with lipopolysaccharide (LPS) and treated with the extract (1, 10 or 100 μg/mL). The resolution of inflammation was accessed by efferocytosis assay. The in vivo anti-inflammatory activity was investigated using carrageenan-induced inflammation in the subcutaneous tissue of male Swiss mice orally treated with the T. erecta extract (30, 100 or 300 mg/kg). The leukocyte influx (optical microscopy), secretion of chemical mediators (TNF, IL-6 and IL-1β, ELISA) and protein exudation (Bradford reaction) were quantified in the inflamed exudate.

RESULTS

In vitro studies demonstrated that the extract inhibited neutrophil chemotaxis and reduced the production and/or release of cytokines (TNF, IL-1β, CXCL1, and IL-6) as well as nitric oxide (NO) by neutrophils and macrophages when stimulated with LPS. Neutrophils treated with LPS and incubated with the extract showed an increase in CD62L expression, which leads to the impairment of neutrophil adhesion. The extract also enhanced efferocytosis of apoptotic neutrophils by macrophages, which was accompanied by increased IL-10 secretion and decreased TNF levels. In vivo studies yielded similar results, showing reduction in neutrophil migration, protein exudation, and cytokine release (TNF, IL-6, and IL-1β).

CONCLUSIONS

Together, the data herein obtained shows that T. erecta flower extract has anti-inflammatory effects by regulating inflammatory mediators, limiting neutrophil migration, and promoting efferocytosis. The in vivo results suggest that an herbal medicine made with T. erecta could represent an interesting pharmacological tool for the treatment of acute inflammatory condition.

Oleanane triterpenoids with C-14 carboxyl group from Astilbe grandis inhibited LPS-induced macrophages activation by suppressing the NF-κB signaling pathway

Background

Excessive inflammation poses significant risks to human physical and mental health. Astilbe grandis, a traditional Miao medicine, is renowned for its anti-inflammatory properties. However, the specific anti-inflammatory effects and mechanisms of many compounds within this plant remain unclear. This study aims to investigate the anti-inflammatory effects and mechanisms of two characteristic oleanane triterpenoids, 3α-acetoxyolean-12-en-27-oic acid (1) and 3β-acetoxyolean-12-en-27-oic acid (2), isolated from Astilbe grandis, using lipopolysaccharide (LPS)-induced Macrophages.

Methods

The anti-inflammatory effects and mechanisms of compounds 1 and 2 were investigated by establishing an LPS-induced inflammation model in RAW 264.7 cells and THP-1 cells. Nitric oxide (NO) levels were assessed using the Griess method. The concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1beta (IL-1β) were measured via enzyme-linked immunosorbent assay (ELISA). The expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) was determined using western blotting and quantitative real-time PCR (qRT-PCR). Additionally, the phosphorylation level of p65 in nuclear factor-kappa B (NF-κB) was assessed through western blotting. The nuclear translocation of NF-κB p65 was assessed through immunofluorescence staining. Finally, the binding affinity of the compounds to NF-κB p65 target was validated through molecular docking.

Results

Compounds 1 and 2 significantly inhibited the expression of NO, TNF-α, IL-6, IL-1β, COX-2, and iNOS in LPS-induced Macrophages. Mechanistically, they attenuated the activation of the NF-κB signaling pathway by downregulating the phosphorylation level and nuclear translocation of p65.

Conclusion

This study elucidates the anti-inflammatory activities and potential mechanism of the characteristic oleanane triterpenoids with C-14 carboxyl group, compounds 1 and 2, in LPS-induced Macrophages by inhibiting the NF-κB signaling pathway for the first time. These findings suggest that these two compounds hold promise as potential candidates for anti-inflammatory interventions in the future.

Vasodilation and Blood Pressure-Lowering Effect of 3-Demethyl-2-Geranyl-4-Prenylbellidifoline, a Xanthone Obtained from Garcinia achachairu, in Hypertensive Rats

3-demethyl-2-geranyl-4-prenylbellidifoline (DGP), a natural xanthone isolated from Garcinia achachairu, has previously demonstrated remarkable diuretic and renal protective actions. The present study expands its actions on the cardiovascular system by evaluating its vasorelaxant and blood pressure-lowering effects in spontaneously hypertensive rats (SHRs). Aortic endothelium-intact (E+) preparations of SHRs pre-contracted by phenylephrine and exposed to cumulative concentrations of G. achachairu extract, fractions, and DGP exhibited a significant relaxation compared to vehicle-only exposed rings. The non-selective muscarinic receptor antagonist (atropine), the non-selective inhibitor of nitric oxide synthase (L-NAME), as well as the inhibitor of soluble guanylate cyclase (ODQ) altogether avoided DGP-induced relaxation. Tetraethylammonium (small conductance Ca2+-activated K+ channel blocker), 4-aminopyridine (a voltage-dependent K+ channel blocker), and barium chloride (an influx-rectifying K+ channel blocker) significantly reduced DGP capacity to induce relaxation without the interference of glibenclamide (an ATP-sensitive inward rectifier 6.1 and 6.2 K+ channel blocker). Additionally, administration of DGP, 1 mg/kg i.v., decreased the mean, systolic, and diastolic arterial pressures, and the heart rate of SHRs. The natural xanthone DGP showed promising potential as an endothelium-dependent vasorelaxant, operating through the nitric oxide pathway and potassium channels, ultimately significantly reducing blood pressure in hypertensive rats.

Effect of Holoptelea integrifolia (Roxb.) Planch. n-Hexane Extract and Its Bioactive Compounds on Wound Healing and Anti-Inflammatory Activity

The stem bark of Holoptelea integrifolia (Roxb.) Planch. has been applied for the treatment of human cutaneous diseases as well as canine demodicosis in several countries. However, no detailed mechanistic studies have been reported to support their use. In this study, thin-layer chromatography and gas chromatography were used to screen phytochemicals from the fresh stem bark extract of H. integrifolia. We found the two major bioactive compounds, friedelin and lupeol, and their activity on wound healing was further investigated in keratinocytes. Both bioactive compounds significantly reduced wound area and increased keratinocyte migration by increasing matrix metalloproteinases-9 production. Subsequently, we found that the mRNA gene expressions of cadherin 1 and desmoglobin 1 significantly decreased, whereas the gene expression involved in keratinocyte proliferation and homeostasis (keratin-17) increased in compound-treated human immortalized keratinocytes cells. The expression of inflammatory genes (cyclooxygenase-2 and inducible nitric oxide synthase) and pro-inflammatory cytokine genes (tumor necrosis factor-alpha and interleukin-6) was reduced by treatment with n-hexane extract of H. integrifolia and its bioactive compounds. Our results revealed that H. integrifolia extract and its bioactive compounds, friedelin and lupeol, exhibit wound-healing activity with anti-inflammatory properties, mediated by regulating the gene expression involved in skin re-epithelialization.

Diuretic and antiurolithic effect of Garcinia humilis (Vahl) C.D.Adams leaves, a medicinal plant native to South American countries

This study evaluated the diuretic and antiurolithic effect of methanolic extract (MEGHL), dichloromethane (DCM), and ethyl acetate (EtA) fractions obtained from the leaves of Garcinia humilis , a medicinal plant known as achachairu and native to South American countries such as Bolivia, Peru, and Brazil. For the analysis of diuretic effect, the female rats received the treatment with MEGHL (3, 10, and 30 mg/kg), DCM (1, 3 and 10 mg/kg), EtA (1, 3, and 10 mg/kg), hydrochlorothiazide (HCTZ; 10 mg/kg), or vehicle (VEH) after an overload of saline solution. At the end 8-h of the experiment, the urinary parameters were measured . Additionally, the antiurolithic effect was analyzed, in which sodium oxalate was added in synthetic urine in the presence or absence of MEGHL, DCM, and EtA in different concentrations (0.1, 0.3, and 1 mg/mL). MEGHL, DCM, and EtA were able to promote 8-h diuresis in rats. MEGHL treatment at dose 30 mg/kg was accompanied by increased urinary Na + , K + and Cl - excretion. Moreover, the DCM and EtA fractions treatment increased K + and Cl - excretion in the urine, although it does not cause any change in Na + elimination. All the preparations were able to exert an antiurolithic effect in vitro , decreasing the number of calcium oxalate crystals of the monohydrate and dihydrate types. Taking together, the results presented herein showed that the preparations of G. humilis leaves are promising strategies to induce diuresis and antiurolithic effects.

Bibliometric review of achachairu (Garcinia humilis): a promising agent for health and future food applications

Abstract The achachairu (Garcinia humilis (Vahl) C.D. Adams) is a Bolivian fruit species that adapts well to tropical and sub-tropical climates and may feasibly be disseminated in other parts of the world. Data from the literature has revealed that both the plant and the fruit exhibited promising compounds for both nutritional and pharmacological purposes. This work aimed to review available publications involving the achachairu (G. humilis) through a bibliometric analysis using data from the Web of Science© (WOS) database. For greater precision and completeness in the research, the filters used included both the scientific nomenclature, and the popular name of the fruit, G. humilis and achachairu, respectively. The data-gathering stage yielded only 29 works containing the terms used in the search. Comprising 25 publications, Brazil was the country having the most records in the database, possibly because its climate is favorable for achachairu cultivation. Among the main research focus areas were attributes related to its chemical structure and pharmacological properties, particularly Guttiferone A, the compound responsible for the gastroprotective, antinociceptive and antiproliferative properties of its fruit, which occurs primarily in its seed. The peel also exhibited a bioactive and antioxidant composition. Thus, these two parts of the fruit, which are considered underutilized, due to the exclusive consumption of the fruit pulp, may have the potential for other purposes. Finally, considering the scarce scientific data regarding this matrix, which has a diversity of positive characteristics for the pharmacological and food industries, this bibliometric analysis revealed an opportunity for further research.

Anti-Inflammatory and Healing Activity of the Hydroalcoholic Fruit Extract of Solanum diploconos (Mart.) Bohs

Background

Solanum diploconos (Mart.) Bohs is a native Brazilian plant belonging to the Solanaceae family, popularly known as “tomatinho do mato” and poorly investigated. Herein, we presented for the first time evidence for the anti-inflammatory and wound healing activities of S. diploconos fruit hydroalcoholic extract. Material and Methods. In vitro fMLP-induced chemotaxis, LPS-induced inflammatory mediator levels (cytokines by ELISA and NO release by Griess reaction), and adhesion molecule expression (CD62L, CD49d, and CD18, by flow-cytometry) were assessed in neutrophils treated with different concentrations of the extract. Inflammation resolution was measured by the efferocytosis assay and the healing activity by in vivo and in vitro assays. The air pouch model of carrageenan-induced inflammation in Swiss mice was used to investigate the in vivo anti-inflammatory effects of the extract. Leukocyte influx (by optical microscopy) and cytokine release were quantified in the pouch exudates. Additionally, the acute and subacute toxic and genotoxic effects of the extract were evaluated.

Results

In vitro, the extract impaired neutrophil chemotaxis and its ability to produce and/or release cytokines (TNFα, IL-1β, and IL-6) and NO upon LPS stimuli (p < 0.01). LPS-treated neutrophils incubated with the extract presented increased CD62L expression (p < 0.01), indicating a reduced activation. An enhanced efferocytosis of apoptotic neutrophils by macrophages was observed and accompanied by higher IL-10 and decreased TNFα secretion (p < 0.01). In vivo, similar results were noted, including reduction of neutrophil migration, protein exudation, and cytokine release (p < 0.01). Also, the extract increased fibroblast proliferation and promoted skin wound healing (p < 0.01). No signs of toxicity or genotoxicity were observed for the extract.

Conclusion

S. diploconos fruit extract is anti-inflammatory by modulating neutrophil migration/activation as well macrophage-dependent efferocytosis and inflammatory mediator release. It also indicates its potential use as a healing agent. Finally, the absence of acute toxic and genotoxic effects reinforces its possible use as medicinal product.

Anti-inflammatory Activity of Mollugo cerviana Methanolic Extract in LPS-induced Acute Inflammatory RAW 264.7 Macrophages

BACKGROUND

The management of acute inflammation, which arises from complex biological responses to harmful stimuli, is an important determinant in recovery of the system from an otherwise detrimental outcome such as septicemia. However, the side effects and limitations of current therapeutics necessitate the development of newer and safer alternatives. Mollugo cerviana is a common medicinal herb of the Indian subcontinent and has been traditionally used for its fever mitigating, anti-microbial and hepatoprotective action. We have already reported the rich presence of radical scavenging phytochemicals in the plant extracts and their strong antioxidant properties.

OBJECTIVE

In the present study, we have evaluated the anti-inflammatory effects of methanolic extract (ME) of the areal parts of M. cerviana in a lipopolysaccharide (LPS)-induced acute inflammatory cell culture model.

METHOD

RAW 264.7 mouse macrophages cell were stimulated by the bacterial endotoxin LPS at a concentration of 1 µg/mL. Cytotoxicity and anti-inflammatory potential of ME were carried out.

RESULTS

M. cerviana extract concentration up to 150 µg/ml was found to be non-toxic to cells (MTT and NRU assay). LPS induces acute inflammation by binding to TLR-4 receptors, initiating downstream signalling cascade that result in pro-inflammatory cytokine secretion. Extract treatment at 100 µg/ml suppressed LPS-induced gene expression (qPCR) and secretion (ELISA) of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α, and the chemokine CCL2, indicating a dampening of the acute inflammatory cascade. LPS-induced elevation of ROS level (DCFDA method) was significant reduced by extract treatment. Nitric oxide production, as indicated by nitrite level, was significantly reduced post extract treatment.

CONCLUSION

From this study, it is demonstrated that M. cerviana methanolic extract has potent anti-inflammatory effect in the in vitro acute inflammation model of LPS-stimulated RAW 264.7 cells. There is not reported study so far on the anti-inflammatory properties of M. cerviana in an LPS-induced acute inflammatory model which closely mimics a human bacteremia response. Hence, this study highlights the therapeutic potential of this extract as a source of anti-inflammatory lead molecules.

Effects of 2',6'-dihydroxy-4'-methoxydihidrochalcone on innate inflammatory response

Chalcones present potential therapeutic activities reported on literature, which led us to evaluate the anti-inflammatory effects and the acute toxicity of 2',6'-dihydroxy-4'-methoxydihydrochalcone (DHMDC) using in vitro and in vivo models. The anti-inflammatory activity was firstly in vitro investigated using macrophages (RAW 264.7) and neutrophils previously treated with DHMCD activated with lipopolysaccharide (LPS). Nitrite, IL-1β, and TNF levels were measured in the macrophage culture supernatant, and the adhesion molecule expression (CD62L, CD49D, and CD18) was evaluated in neutrophils. Then, carrageenan-induced inflammation was performed in the subcutaneous tissue of male Swiss mice. Leukocyte migration and histological analysis were performed in the pouches. Toxicological studies were carried out on female Swiss mice (600 mg/kg) through biochemical parameters and histopathological analysis. In vitro, the DHMCD significantly reduced the IL-1β, TNF, and nitrite levels. The DHMCD was also able to modulate the percentage of positive neutrophils for CD62L, without modifying the expression of CD18 or CD49d. In vivo, DHMCD (3 mg/kg, p.o.) significantly reduced neutrophil migration to inflammatory exudate and subcutaneous tissue. No evidence of toxic effect was observed considering the biochemical parameters and histopathological analysis of liver and kidney. Together, the obtained data shows that DHMCD presents anti-inflammatory activity by modulating the macrophage inflammatory protein secretion and also by blocking the CD62L cleavage in neutrophils. Furthermore, there was not any evidence of toxic effect in acute toxicological analysis.