An analysis method for simultaneous screening of deoxyribonucleic acid-binding active compounds and investigating their mechanisms by ultra-fast liquid chromatography tandem mass spectrometry coupled with fluorescence detection technology

Characterization and identification of major flavonoids of bamboo leaf extract by HPLC/ESI-QTOF-MS/MS

Bamboo leaf extract (BLE) is a pale brown powder extracted from bamboo leaves, and it is listed in the Chinese Standard GB-2760 as a legal and safe food additive. The present study aims to identify and characterize the major flavonoids in BLE. The identification of major flavonoids was carried out using ultra performance liquid chromatography combined with electrospray ionization quadruple time-of-flight tandem mass spectrometry (HPLC/ESI-QTOF-MS/MS). A total of 31 flavonoid compounds were identified and tentatively characterized base on reference standards and MS dissociation mechanisms. HPLC/ESI-QTOF-MS can serve as an important analytical platform to identification structure of bamboo leaf flavonoids (BLF).

Lophatherum gracile Bronghiart Suppresses Receptor Activator of Nuclear Factor Kappa-B Ligand-Stimulated Osteoclastogenesis and Prevents Ovariectomy-Induced Osteoporosis

Lophatherum gracile Bronghiart, used in traditional herbal medicine, has many biological properties including antiviral, antipyretic, antitumor, vasorelaxation, and neutrophilic inflammatory effects. However, its modulatory effects on bone metabolism have not been investigated previously. In this study, we examined the effects of a water extract of the leaves of L. gracile (WELG) on osteoclast differentiation and bone loss, and explored its underlying mechanisms. We found that WELG inhibits osteoclastogenesis by suppressing both receptor activator of nuclear factor-κB ligand (RANKL)-induced early activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB)- and RANKL-induced modulation of the positive and negative regulators of osteoclastogenesis in osteoclast precursors. In vivo study demonstrated that WELG protects against bone loss, weight gain, and fat accumulation without affecting uterine atrophy in an ovariectomy-induced postmenopausal osteoporosis mice model. In addition, photochemical analysis of WELG identified active constituents known to have bone-protective effects. Overall, the results of this study suggest that WELG can be a potential candidate for therapy and prevention of postmenopausal osteoporosis.

Ethanolic extract of Pyrrosia lingua (Thunb.) Farw. ameliorates OVX-induced bone loss and RANKL-induced osteoclastogenesis

Pyrrosia lingua (Thunb.) Farw is a common plant that has been widely used as a traditional herbal medicine in China and Korea to treat patients suffering from pain, vaginal bleeding and urolithiasis. However, the pharmacological effects of P. lingua on bone remain unknown. We investigated the anti-osteoporotic effects of an ethanolic extract of P. lingua (EEPL). We found that EEPL suppressed osteoclast differentiation by directly acting on osteoclast precursor cells. EEPL suppressed the expression of receptor activator of nuclear factor-κB ligand (RANKL)-induced nuclear factor of activated T cells 1, a major transcription factor for osteoclastogenesis, by inhibiting RANKL-induced expression of aryl hydrocarbon receptor/c-Fos, and activation of nuclear factor-κB and mitogen-activated protein kinases. Moreover, administration of EEPL inhibited trabecular bone loss and weight gain in ovariectomized mice. Furthermore, we identified phytochemicals in EEPL that are known to exert anti-osteoclastogenic or anti-osteoporotic effects using ultra-high-performance liquid chromatography-tandem mass-spectrometry analysis. Overall, the results of this study suggest that EEPL is effective therapeutic candidate that can be used to prevent or treat postmenopausal osteoporosis.

Mechanistic new insights of flavonols on neurodegenerative diseases

With a large and increasing elderly population, neurodegenerative diseases such as Parkinson's disease (PD), Huntington disease (HD), Alzheimer's disease (AD), Amyotrophic lateral sclerosis (ALS) and Multiple sclerosis (MS) have become a major and growing health problem. During the past few decades, the elderly population has grown 2.5 % every year. Unfortunately, there are no specific therapeutic remedies available to slow the onset or development of these diseases. An aging brain causes many pathophysiological changes and is the major risk factor for most of the neurodegenerative disorders. Polyphenolic compounds such as flavonols have shown therapeutic potential and can contribute to the treatment of these diseases. In this review, evidence for the beneficial neuroprotective effect of multiple flavonols is discussed and their multifactorial cellular pathways for the progressions of age-associated brain changes are identified. Moreover, the animal models of these diseases support the neuroprotective effect and target the potential of flavonols in the treatment of neurodegenerative diseases.

Rapid Screening of Potential Phosphodiesterase Inhibitors from the Roots of Ilex pubescens Hook. et Arn. Using a Combination of Ultrafiltration and LC-MS

The cyclic nucleotide phosphodiesterase (PDE) plays an important role in regulating the levels of second messenger molecules cAMP and cGMP. Various PDE inhibitors have been successfully developed into drugs for targeted diseases. In addition, PDE inhibitors can also be found in different foods and natural medicines. In this study, ultrafiltration liquid chromatography-diode-array detector-electrospray ionization-ion-trap-time-of-flight-mass spectrometry (ultrafiltration LC-DAD-ESI-IT-TOF-MS) was applied to screen PDE inhibitors from the roots of Ilex pubescens Hook. et Arn. As a result, 11 major compounds were identified in I. pubescens roots, with nine compounds as potential PDE inhibitors, among which five were further confirmed to be active against PDEI and PDE5A dose-dependently in vitro, with ilexsaponin A1 and ilexsaponin B2 being the strongest. HPLC quantification of these bioactive compounds suggested that they are major components in the plant. The results demonstrate that ultrafiltration LC-DAD-ESI-IT-TOF-MS is an efficient method for rapid screening of PDE inhibitors from natural medicines.

Rapid Identification and Assignation of the Active Ingredients in Fufang Banbianlian Injection Using HPLC-DAD-ESI-IT-TOF-MS

Fufang Banbianlian Injection (FBI) is a well-known traditional Chinese medicine formula composed of three herbal medicines. However, the systematic investigation on its chemical components has not been reported yet. In this study, a high-performance liquid chromatography combined with diode-array detector, and coupled to an electrospray ionization with ion-trap time-of-flight mass spectrometry (HPLC-DAD-ESI-IT-TOF-MS) method, was established for the identification of chemical profile in FBI. Sixty-six major constituents (14 phenolic acids, 14 iridoids, 20 flavonoids, 2 benzylideneacetone compounds, 3 phenylethanoid glycosides, 1 coumarin, 1 lignan, 3 nucleosides, 1 amino acids, 1 monosaccharides, 2 oligosaccharides, 3 alduronic acids and citric acid) were identified or tentatively characterized by comparing their retention times and MS spectra with those of standards or literature data. Finally, all constituents were further assigned in the individual herbs (InHs), although some of them were from multiple InHs. As a result, 11 compounds were from Lobelia chinensis Lour, 33 compounds were from Scutellaria barbata D. Don and 38 compounds were from Hedyotis diffusa Willd. In conclusion, the developed HPLC-DAD-ESI-IT-TOF-MS method is a rapid and efficient technique for analysis of FBI sample, and could be a valuable method for the further study on the quality control of the FBI.