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1.
J Ethnopharmacol ; 306: 116148, 2023 Apr 24.
Article in English | MEDLINE | ID: mdl-36634723

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Betula pendula subsp. Mandshurica (Regel) Ashburner & McAll. Cortex (birch bark) is a globally traditional medicine for treating multiple inflammatory diseases. Its records are included in the Compendium of Materia Medica and other ancient medical literatures. However, uncovering its chemical profile and exploring novel biologically active compounds from birch bark remains a significant challenge. AIM OF THE STUDY: To uncover the anti-inflammatory, -oxidative, and -proliferative mechanisms and potentially effective compounds of birch bark extract by combing chemical profiling, isolation, identification, together with in vivo, in vitro, and silico evaluation. MATERIALS AND METHODS: Ultra-performance liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS) was used to obtain the chemical profile of birch bark extract. The new compounds were obtained via column chromatography and analyzed using X-ray diffraction and electronic circular dichroism for absolute configuration confirmation. The zebrafish caudal fin inflammation-induced model, qPCR, and Western blot analysis were used to explore the effects and underlying mechanisms of birch bark extract. In vitro cytotoxicity assays and kinases screening conducted to gain preliminary insight into the anti-proliferative effects of birch bark extract and its isolated compounds. In addition, in-silico molecular docking was performed to investigate the putative mechanism. RESULTS: UPLC-QTOF-MS/MS chemical profiles revealed 105 compounds in birch bark extract, with 80 of these were first reported in B. pendula subsp. Mandshurica cortex. We selected five compounds speculated as novel and isolated three ones (one triterpenoid derivative and two lupine series triterpenoids) for further analysis. Birch bark extract exerted antioxidative and anti-inflammatory effects on zebrafish, as shown by the downregulated reactive oxygen species levels and COX-2α, IL-1ß, and TNF-α expression, which occurred through NF-ĸB signaling pathway activation. The in vitro anti-proliferative effects of birch bark extract and compound 44 were also unveiled. Moreover, the putative anti-tumor mechanism of compound 44 was revealed using kinase screening and in-silico molecular docking. CONCLUSIONS: This study provided a predictable chemical profile and demonstrated the pharmacological effects of birch bark extract, elucidated the mechanism of this traditional Chinese medicine and suggested it as a novel anti-cancer candidate.


Subject(s)
Tandem Mass Spectrometry , Triterpenes , Animals , Tandem Mass Spectrometry/methods , Betula/chemistry , Plant Extracts/pharmacology , Zebrafish , Plant Bark/chemistry , Molecular Docking Simulation , Anti-Inflammatory Agents/pharmacology , Triterpenes/pharmacology , Oxidative Stress , Chromatography, High Pressure Liquid/methods
2.
Basic Clin Pharmacol Toxicol ; 128(2): 275-285, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33012100

ABSTRACT

QF-036 is an HIV-1 maturation inhibitor in pre-clinical development, and its antiviral activity against a laboratory HIV-1 strain and two drug-resistant strains was determined in the C8166 line. QF-036 was also subjected to absorption, distribution and metabolism (ADM) assessment in vitro, and pharmacokinetic profiles were evaluated in rats and monkeys. The 50% effective concentrations (EC50 ) of QF-036 against the three strains were 20.36 nM, 0.39 µM and 2.11 nM, respectively, demonstrating better antiviral potential than the first-generation antiviral maturation inhibitor bevirimat. QF-036 demonstrated moderate cell permeability, high plasma protein binding ability and good metabolic stability in vitro. After oral QF-036 administration to rats and monkeys, both species exhibited moderate bioavailability, and the plasma drug exposure increased in an approximately dose-proportional manner. When administered orally (30 mg/kg) to monkeys, the QF-036 plasma concentration (Cmax ) peaked at 3671 ng/mL (4.82 µM), 12 to 2410 times higher than the EC50 of laboratory or resistant HIV-1 strains. Moreover, the plasma concentration of QF-036 at 12 hours after administration was 263 ng/mL (0.35 µM), which approximately matched the highest EC50 value of the three test strains. The favourable viral inhibitory activity and pharmacokinetic properties provide critical support for QF-036 as a promising anti-HIV therapeutic candidate.


Subject(s)
Anti-HIV Agents/pharmacology , HIV-1/drug effects , Triterpenes/pharmacology , Virus Replication/drug effects , Administration, Oral , Animals , Anti-HIV Agents/administration & dosage , Anti-HIV Agents/pharmacokinetics , Biological Availability , Caco-2 Cells , Dogs , Drug Resistance, Viral , Female , Gastrointestinal Absorption , HIV-1/genetics , HIV-1/growth & development , Humans , Macaca fascicularis , Male , Mice , Rats, Sprague-Dawley , Succinates/pharmacology
3.
Toxicol Lett ; 329: 26-30, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-32380124

ABSTRACT

QF-036 is a novel human immunodeficiency virus (HIV) maturation inhibitor that is a lupine triterpenoid derivative. The objective of this study was to evaluate the safety of QF-036. A single oral toxicity and a 4-week repeated oral toxicity were investigated in Sprague-Dawley (SD) rats. The single oral toxicity study of QF-036 in SD rats showed that no mortality or visible pathological changes were noted at doses of 100, 300, and 1000 mg/kg. QF-036 exhibited a non-linear toxicokinetic profile over the dose range of 100-1000 mg/kg in the single dose study, and a saturation trend appeared at doses of 100 and 300 mg/kg. In the 4-week oral toxicity and toxicokinetic study, SD rats were given 0, 50, 100, and 200 mg/kg QF-036 once daily for 4 weeks, followed by a 4-week recovery period. No mortality or significant effects on food consumption, body weight, or behavior were observed. In addition, there were no test article-related changes in hematology, clinical biochemistry and histopathology. The no observed adverse effect level (NOAEL) was 200 mg/kg. The toxicokinetic study demonstrated a dose-dependent increase in the systemic exposure to QF-036 after 4 weeks of oral administration. There were no marked sex differences or drug accumulation observed for repeated doses of QF-036.


Subject(s)
Anti-HIV Agents/toxicity , Triterpenes/pharmacology , Administration, Oral , Animals , Anti-HIV Agents/administration & dosage , Anti-HIV Agents/chemistry , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Male , Molecular Structure , Rats , Rats, Sprague-Dawley , Toxicity Tests , Triterpenes/toxicity
4.
J Hum Evol ; 78: 144-57, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25456822

ABSTRACT

The Homo erectus cranium from Gongwangling, Lantian County, Shaanxi Province is the oldest fossil hominin specimen from North China. It was found in 1964 in a layer below the Jaramillo subchron and was attributed to loess (L) L15 in the Chinese loess-palaeosol sequence, with an estimated age of ca. 1.15 Ma (millions of years ago). Here, we demonstrate that there is a stratigraphical hiatus in the Gongwangling section immediately below loess 15, and the cranium in fact lies in palaeosol (S) S22 or S23, the age of which is ca. 1.54-1.65 Ma. Closely spaced palaeomagnetic sampling at two sections at Gongwangling and one at Jiacun, 10 km to the north, indicate that the fossil layer at Gongwangling and a similar fossil horizon at Jiacun were deposited shortly before a short period of normal polarity above the Olduvai subchron. This is attributed to the Gilsa Event that has been dated elsewhere to ca. 1.62 Ma. Our investigations thus demonstrate that the Gongwangling cranium is slightly older than ca. 1.62 Ma, probably ca. 1.63 Ma, and significantly older than previously supposed. This re-dating now makes Gongwangling the second oldest site outside Africa (after Dmanisi) with cranial remains, and causes substantial re-adjustment in the early fossil hominin record in Eurasia.


Subject(s)
Hominidae/anatomy & histology , Skull/anatomy & histology , Animals , China , Fossils , Paleontology , Radiometric Dating
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