Nelumbo nucifera leaves extracts inhibit mouse airway smooth muscle contraction

The peels of sacred Lotus (Nelumbo nucifera) rhizomes suppress allergic reactions by inhibiting the A23187-induced degranulation in rat basophilic leukemia (RBL2H3) cells

We isolated ten compounds from methanolic extract of the peels of sacred lotus (Nelumbo nucifera) rhizomes which were identified as β-sitosterol linoleate 1, β-sitosterol 2, lupeol 3, stigmasterol 3-O-β-D-glucoside 4, oleanolic acid 5, betulinic acid 6, pinoresinol 7, 4-hydroxybenzoic acid 8, catechin 9 and gallocatechin 10. All of the isolated compounds from the peels of sacred lotus rhizomes are reported for the first time, and were investigated for their anti-allergic activity. We found that three of them, stigmasterol 3-O-β-D-glucoside 4, oleanolic acid 5 and pinoresinol 7, were capable of inhibiting A23187-induced degranulation in RBL-2H3 cells with IC50 values 0.18 ± 0.01 mM, 0.28 ± 0.06 mM, and 0.27 ± 0.01 mM, respectively. With an exception to 4, compounds 5 and 7 achieved the anti-allergic effect without affecting the cells viability even at higher concentrations with their selectivity indices (SI) being >5. By reducing A23187-induced degranulation, it is suggestive of a mechanism attenuation of Ca2+ elevation. Our findings suggest that, the peels of sacred lotus rhizomes would be beneficial for providing an inexpensive source for the production of bioactive compounds with anti-allergic effect.

Coptisine, a protoberberine alkaloid, relaxes mouse airway smooth muscle via blockade of VDLCCs and NSCCs

Background/Aims: Recently, effective and purified ingredients of traditional Chinese medicine (TCM) were extracted to play crucial roles in the treatment of pulmonary diseases. Our previous research focused on TCM drug screening aimed at abnormal airway muscle contraction during respiratory diseases. Coptisine, an effective ingredient extracted from bitter herbs has shown a series of antioxidant, antibacterial, cardioprotective and neuroprotective pharmacological properties. In the current study, we questioned whether coptisine could also participate in asthma treatment through relaxing abnormal contracted mouse airway smooth muscle (ASM). The present study aimed to characterize the relaxant effects of coptisine on mouse ASM and uncover the underlying molecular mechanisms. Methods: To investigate the role of coptisine on pre-contracted mouse ASM, a series of biological techniques, including force measurement and patch-clamp experiments were employed. Results: Coptisine was found to inhibit high K⁺ or acetylcholine chloride (ACh)-induced pre-contracted mouse tracheal rings in a dose-dependent manner. Further research demonstrated that the coptisine-induced mouse ASM relaxation was mediated by alteration of calcium mobilization via voltage-dependent L-type Ca²⁺ channels (VDLCCs) and non-selective cation channels (NSCCs). Conclusion: Our data showed that mouse ASM could be relaxed by coptisine via altering the intracellular Ca²⁺ concentration through blocking VDLCCs and NSCCs, which suggested that this pharmacological active constituent might be classified as a potential new drug for the treatment of abnormal airway muscle contraction.

Aster tataricus attenuates asthma efficiently by simultaneously inhibiting tracheal ring contraction and inflammation

Asthma is an airway chronic inflammatory disease with significant morbidity, mortality and huge social economic burden. Previous research demonstrated that the root of Aster tataricus (RA) may have the potential to treat asthma, but the efficacy and mechanism were not clear. In this study, preliminary results in vitro showed that Fr-75 eluted from RA extract could not only completely inhibit the tracheal ring contraction raised by KCl in 20 min, but also effectively affect the tracheal ring contraction induced by KCl-, Ach- and His in a concentration-dependent manner (3.91-250 μg/mL). Further results on cells exhibited that Fr-75 could decrease the concentration of intracellular Ca²⁺ as well. These results revealed the underlying mechanism in vitro that the inhibition of tracheal ring contraction might be due to the decline of the intracellular Ca²⁺ concentration, which caused by suppressing calcium channel, antagonizing the muscarinic and histamine receptors. Also, results in vivo exhibited that Fr-75 could distinctly ease the symptoms of ovalbumin-sensitized mice, including relieving the pathological injury, increasing the latency to preconvulsive dyspnea and to enhanced pause, reducing the inflammatory cells, chemokines and cytokines in BALF and lung tissue. In general, it could be speculated that RA fraction may attenuate asthma through dilating the tracheal ring contraction and alleviating the lung inflammation simultaneously.

Use of Natural Products in Asthma Treatment

Asthma, a disease classified as a chronic inflammatory disorder induced by airway inflammation, is triggered by a genetic predisposition or antigen sensitization. Drugs currently used as therapies present disadvantages such as high cost and side effects, which compromise the treatment compliance. Alternatively, traditional medicine has reported the use of natural products as alternative or complementary treatment. The aim of this review was to summarize the knowledge reported in the literature about the use of natural products for asthma treatment. The search strategy included scientific studies published between January 2006 and December 2017, using the keywords "asthma," "treatment," and "natural products." The inclusion criteria were as follows: (i) studies that aimed at elucidating the antiasthmatic activity of natural-based compounds or extracts using laboratory experiments (in vitro and/or in vivo); and (ii) studies that suggested the use of natural products in asthma treatment by elucidation of its chemical composition. Studies that (i) did not report experimental data and (ii) manuscripts in languages other than English were excluded. Based on the findings from the literature search, aspects related to asthma physiopathology, epidemiology, and conventional treatment were discussed. Then, several studies reporting the effectiveness of natural products in the asthma treatment were presented, highlighting plants as the main source. Moreover, natural products from animals and microorganisms were also discussed and their high potential in the antiasthmatic therapy was emphasized. This review highlighted the importance of natural products as an alternative and/or complementary treatment source for asthma treatment, since they present reduced side effects and comparable effectiveness as the drugs currently used on treatment protocols.

Relaxant Action of Diclofenac Sodium on Mouse Airway Smooth Muscle

Diclofenac sodium (DCF) is a nonsteroidal anti-inflammatory drug (NSAID) and is widely used as an analgesic and anti-inflammatory agent. Herein, we found that DCF could relax high K+ (80 mM K+)-/ACh-precontracted tracheal rings (TRs) in mice. This study aimed to elucidate the underlying mechanisms of DCF-induced relaxations. The effects of DCF on airway smooth muscle (ASM) cells were explored using multiple biophysiological techniques, such as isometric tension measurement and patch-clamping experiments. Both high K+- and ACh-evoked contraction of TRs in mice were relaxed by DCF in a dose-dependent manner. The results of isometric tension and patch-clamping experiments demonstrated that DCF-induced relaxation in ASM cells was mediated by cytosolic free Ca2+, which was decreased via inhibition of voltage-dependent L-type Ca2+ channels (VDLCCs), nonselective cation channels (NSCCs), and Na+/Ca2+ exchange. Meanwhile, DCF also enhanced large conductance Ca2+ activated K+ (BK) channels, which led to the relaxation of ASMs. Our data demonstrated that DCF relaxed ASMs by decreasing the intracellular Ca2+ concentration via inhibition of Ca2+ influx and Na+/Ca2+ exchange. Meanwhile, the enhanced BK channels also played a role in DCF-induced relaxation in ASMs. These results suggest that DCF is a potential candidate for antibronchospasmic drugs used in treating respiratory diseases such as asthma and chronic obstructive pulmonary disease.

Assessing the recovery from prerenal and renal acute kidney injury after treatment with single herbal medicine via activity of the biomarkers HMGB1, NGAL and KIM-1 in kidney proximal tubular cells treated by cisplatin with different doses and exposure times

Background

Acute kidney injury (AKI) is an initial factor in many kidney disorders. Pre- and intra-renal AKI biomarkers have recently been reported. Recovery from AKI by herbal medicine has rarely been reported. Thus, this study aimed to investigate the dose- and time-dependent effects of herbal medicines to protect against AKI in cisplatin-induced human kidney 2 (HK-2) cells by assessing the activities of high-mobility group box protein 1 (HMGB1), neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1).

Methods

Proximal tubular HK-2 cell lines were treated with either 400 μM of cisplatin for 6 h or 10 μM of cisplatin for 24 h and then exposed to ten types of single herbal medicines, including Nelumbo nymphaea (NY) at a dose of 100 μg/mL. The AKI biomarkers HMGB1, NGAL and KIM-1 were repeatedly measured by an ELISA assay at 2, 4, and 6 h in the group treated with 400 μM of cisplatin to confirm necrotic cell death and at 6, 24, and 48 h in the group treated with 10 μM of cisplatin to examine apoptotic cell death. Recovery confirm was conducted through in vivo study using ICR mice for 3 day NY or Paeonia suffruticosa intake.

Results

Cisplatin treatment at a concentration of 10 μM decreased cell viability. Treatment with 400 μM of cisplatin reduced HMBG1 activity and resulted in lactate dehydrogenase release. In longer exposure durations (up to 48 h), NGAL and KIM-1 exhibited activity from 24 h onward. Additionally, NY treatment resulted in an approximately 50% change in all three biomarkers. The time-dependent profiles of HMGB1, NGAL and KIM-1 activities up to 48 h were notably different; HMGB1 exhibited a 7-fold change at 6 h, and NGAL and KIM-1 exhibited 1.7-fold changes at 24 h, respectively. Consistently, serum and urine NGAL and KIM-1 activities were all reduced in ICR mice.

Conclusions

Several single herbal medicines, including NY, have a potential as effectors of AKI due to their ability to inhibit the activation of HMGB1, NGAL and KIM-1 in an in vitro AKI-mimicked condition and simple in vivo confirm. Furthermore, an in vivo proof-of-concept study is needed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-017-2055-y) contains supplementary material, which is available to authorized users.