Calcium and potassium channels are involved in curcumin relaxant effect on tracheal smooth muscles

Evaluation of nano-curcumin against inhaled paraquat-induced lung injury in rats

BACKGROUND

Acute lung injury (ALI) remains a significant source of morbidity and mortality in critically ill patients and currently there is no efficient therapy for this condition. The aim of this research was to evaluate the protective activity of nano-curcumin (nano-CU) as a natural anti-inflammatory and antioxidant agent, against inhaled paraquat (PQ)-induced lung injury.

METHODS

One group of rats was exposed to saline (control group, Ctrl) and six groups to PQ aerosol (54 mg/m³ on alternate days 8 times, each time for 30 min) treated with drinking water alone (group PQ), 2 and 8 mg/kg nano-CU (nano + CU(L) and nano + CU(H)), 5 mg/kg pioglitazone (PIO), nano-CU(L) + PIO or 0.03 mg/kg dexamethasone (Dexa) for 16 days after PQ exposure period. PIO and Dexa were intraperitoneal (ip) injected and nano-CU was administered orally (po), (6 rats in each group).

RESULTS

In the PQ group, total and differential WBC counts, malondialdehyde (MDA) in the bronchoalveolar lavage fluid (BALF), interferon gamma (INF-γ) and interleukin 10 (IL-10) levels in the lung tissues, lung pathological changes, and tracheal responsiveness were increased but the BALF thiol, catalase (CAT) and superoxide dismutase (SOD) levels were reduced. In treated groups with nano-CU(H) and PIO + nano-CU(L), all measured variables, in Dexa and nano-CU(L) treated groups, most variables and in the PIO group only a few variables were improved. The improvement of most variables in the PIO + nano-CU(L) group was significantly higher than in the PIO and nano-CU(L) groups alone.

CONCLUSIONS

Nano-CU ameliorated lung damage induced by inhaled PQ similar to dexa and a synergic effect between nano-CU and PIO was observed, suggesting, a possible PPAR-γ receptor-mediated effect of curcumin.

Paraquat-induced systemic inflammation and oxidative stress in rats improved by Curcuma longa ethanolic extract, curcumin and a PPAR agonist

The effect of Curcuma longa (Cl) ethanolic extract, nano-curcumin (Cu) and a PPARγ activator, pioglitazone on inhaled paraquat (PQ)-induced systemic inflammation and oxidative stress was examined in the present study. Control rats were exposed to normal saline and PQ groups to 27 and 54 mg/m³ (PQ-L and PQ-H) aerosols. Nine other PQ-H groups were treated with Curcuma longa (Cl, 150 and 600 mg/kg/day), nano-curcumin (Cu, 2 and 8 mg/kg/day), pioglitazone (Pio, 5 and 10 mg/kg), low dose of Pio + Cl and Cu and dexamethasone (0.03 mg/kg/day) for 16 days after PQ exposure period (n = 8). Total and differential WBC counts, malondialdehyde (MDA) and TNF-α levels were increased but thiol, catalase (CAT), superoxide dismutase (SOD), IL-10 and IFN-γ levels were decreased in the blood in the both PQ groups (p < 0.05 to p < 0.001). Treatment with Dexa and both doses of Cl, Cu, and Pio improved all measured variables compared to the PQ-H group (p < 0.05 to p < 0.001). The improvements of most variables in the treated group with low dose of Pio + Cl and Cu were higher than the effects of three agents alone. Systemic inflammation and oxidative stress induced by inhaled PQ were improved by Cl, Cu and Pio. In addition, a synergic effect between Pio with those of Cl and Cu was shown, suggesting PPARγ mediated effects of the plant and its derivative Cu.

Preliminary Mechanistic Study on the Trachea Smooth Muscle Relaxant Activity of Aqueous Leaf Extract of Tridax Procumbens in Male Wistar Rats

Objectives

Aqueous leaf extract of Tridax procumbens (ALETP) has potent relaxant activity. However, this relaxant activity in respiratory smooth muscle remains uninvestigated. This study investigates the effect of ALETP on the contractile activity of tracheal smooth muscle (TSM) in adult male Wistar rats.

Methods

Twelve male Wistar rats divided into 2 groups and were treated with either 100 mg/kg of ALETP (ALETP treatment group) or vehicle (distilled water; control group) through oral gavage for 4 weeks. Dose responses of TSM from the 2 groups to acetylcholine (10^–9 to 10^–5 M), phenylephrine (10^–9 to 10^–5 M), and potassium chloride (KCl; 10^–9 to 10^–4 M) were determined cumulatively. Furthermore, cumulative dose responses to acetylcholine (10^–9 to 10^–5 M) after pre-incubation of TSM with atropine (10^–5 M), L-NAME (10^–4 M), indomethacin (10^–4 M), and nifedipine (10^–4 M), were determined.

Results

Treatment with ALETP substantially inhibited TSM contraction stimulated by cumulative doses of acetylcholine, phenylephrine, and KCl. Furthermore, preincubation of TSM from the 2 groups in atropine significantly inhibited contractility in TSM. Incubation in L-NAME and indomethacin also significantly inhibited contractility in TSM of ALETP-treated rats compared to that of controls. Contractile activity of the TSM was also inhibited significantly with incubation in nifedipine in ALETP-treated rats.

Conclusion

ALETP enhanced relaxant activity in rat TSM primarily by blocking the L-type calcium channel and promoting endothelial nitric oxide release. ALETP contains agents that may be useful in disorders of the respiratory tract.

Role of curcumin in selected head and neck lesions. Limitations on the use of the Hep-2 cell line: A critical review

Neoplastic diseases of the upper respiratory airways, as well as head and neck cancers, are a frequent cause of death and significantly affect the quality of life of both patients and survivors. As the frequency increases, new and improved treatment techniques are sought. Promising properties in this respect are expressed by a natural compound - curcumin. Along with its derivatives, it was found useful in the treatment of a series of cancers. Curcumin was found to be effective in clinical trials and in vitro, in vivo anticancer experiments. Nanoformulations (e.g., poly(lactide-co-glycolic acid)-based nanoparticles, nanoemulsions), and modifications of curcumin, as well as its combinations with other substances (e.g., catechins, cisplatin) or treatments (e.g., radiotherapy or local use in inhalation), were found to enhance the antitumor effect. This review aims to summarize the recent findings for the treatment of head and neck diseases, especially squamous cell carcinomas (HNSCCs), including drawing attention to the constant use of the misidentified Hep-2 cell line and proposing databases purposed at eliminating this problem. Moreover, this manuscript focuses on pointing out the molecular mechanisms of therapy that have been reached and emphasizing the shortcomings that still need to be addressed.

Curcuma longa and curcumin affect respiratory and allergic disorders, experimental and clinical evidence: A comprehensive and updated review

Curcuma longa and its constituents, mainly curcumin, showed various of pharmacological effects in previous studies. This review article provides updated and comprehensive experimental and clinical evidence regarding the effects of C. longa and curcumin on respiratory, allergic, and immunologic disorders. Using appropriate keywords, databases including PubMed, Science Direct, and Scopus were searched until the end of October 2021. C. longa extracts and its constituent, curcumin, showed the relaxant effect on tracheal smooth muscle, which indicates their bronchodilatory effect in obstructive pulmonary diseases. The preventive effects of extracts of C. longa and curcumin were shown in experimental animal models of different respiratory diseases through antioxidant, immunomodulatory, and anti-inflammatory mechanisms. C. longa and curcumin also showed preventive effects on some lung disorders in the clinical studies. It was shown that the effects of C. longa on pulmonary diseases were mainly due to its constituent, curcumin. Pharmacological effects of C. longa extracts and curcumin on respiratory, allergic, and immunologic disorders indicate the possible therapeutic effect of the plant and curcumin on these diseases.

Genomics approaches to synthesize plant-based biomolecules for therapeutic applications to combat SARS-CoV-2

COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is devastative to the humankind for which neither vaccines nor precise therapeutic molecules for treatment are identified. The search for new drugs and repurposing of existing drugs are being performed; however, at the same time, research on plants to identify novel therapeutic compounds or testing the existing ones is progressing at a slower phase. In this context, genomics and biotechnology offer various tools and strategies to manipulate plants for producing those complex biopharmaceutical products. This review enumerates the scope for research on plant-based molecules for their potential application in treating SARS-CoV-2 infection. Strategies to edit gene and genome, overexpression and silencing approaches, and molecular breeding for producing target biomolecules in the plant system are discussed in detail. Altogether, the present review provides a roadmap for expediting research on using plants as a novel source of active biomolecules having therapeutic applications.

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Plants are a source of biomolecules that have application in treatment of SARS-CoV-2.

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Identifying active biomolecules for therapeutic purposes is not adequately performed.

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High-throughput strategies promote large-scale screening of plant-based drugs.

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Plant biotechnology facilitates the production of complex biopharmaceutical products.