The regulation of the PD-1/PD-L1 pathway in imiquimod-induced chronic psoriasis itch and itch sensitization in mouse.

PD-1/PD-L1 inhibitors have been demonstrated to induce itch in both humans and experimental animals. However, whether the PD-1/PD-L1 pathway is involved in the regulation of chronic psoriatic itch remains unclear. This study aimed to investigate the role of the PD-1/PD-L1 pathway in imiquimod-induced chronic psoriatic itch. The intradermal injection of PD-L1 in the nape of neck significantly alleviated chronic psoriatic itch in imiquimod-treated skin. Additionally, we observed that spontaneous scratching behavior induced by imiquimod disappeared on day 21. Still, intradermal injection of PD-1/PD-L1 inhibitors could induce more spontaneous scratching for over a month, indicating that imiquimod-treated skin remained in an itch sensitization state after the spontaneous scratching behavior disappeared. During this period, there was a significant increase in PD-1 receptor expression in both the imiquimod-treated skin and the spinal dorsal horn in mice, accompanied by significant activation of microglia in the spinal dorsal horn. These findings suggest the potential involvement of the peripheral and central PD-1/PD-L1 pathways in regulating chronic itch and itch sensitization induced by imiquimod.

Hydrogen Sulfide Exerted a Pro-Angiogenic Role by Promoting the Phosphorylation of VEGFR2 at Tyr797 and Ser799 Sites in Hypoxia-Reoxygenation Injury.

The protective effects of hydrogen sulfide (H2S) against ischemic brain injury and its role in promoting angiogenesis have been established. However, the specific mechanism underlying these effects remains unclear. This study is designed to investigate the regulatory impact and mechanism of H2S on VEGFR2 phosphorylation. Following expression and purification, the recombinant His-VEGFR2 protein was subjected to LC-PRM/MS analysis to identify the phosphorylation sites of VEGFR2 upon NaHS treatment. Adenovirus infection was used to transfect primary rat brain artery endothelial cells (BAECs) with the Ad-VEGFR2WT, Ad-VEGFR2Y797F, and Ad-VEGFR2S799A plasmids. The expression of VEGFR2 and recombinant Flag-VEGFR2, along with Akt phosphorylation, cell proliferation, and LDH levels, was assessed. The migratory capacity and tube-forming potential of BAECs were assessed using wound healing, transwell, and tube formation assays. NaHS notably enhanced the phosphorylation of VEGFR2 at Tyr797 and Ser799 sites. These phosphorylation sites were identified as crucial for mediating the protective effects of NaHS against hypoxia-reoxygenation (H/R) injury. NaHS significantly enhanced the Akt phosphorylation, migratory capacity, and tube formation of BAECs and upregulated the expression of VEGFR2 and recombinant proteins. These findings suggest that Tyr797 and Ser799 sites of VEGFR2 serve as crucial mediators of H2S-induced pro-angiogenic effects and protection against H/R injury.

Cu(I)-Catalyzed Chemo- and Enantioselective Desymmetrizing C-O Bond Coupling of Acyl Radicals.

Transition-metal-catalyzed enantioselective functionalization of acyl radicals has so far not been realized, probably due to their relatively high reactivity, which renders the chemo- and stereocontrol challenging. Herein, we describe Cu(I)-catalyzed enantioselective desymmetrizing C-O bond coupling of acyl radicals. This reaction is compatible with (hetero)aryl and alkyl aldehydes and, more importantly, displays a very broad scope of challenging alcohol substrates, such as 2,2-disubstituted 1,3-diols, 2-substituted-2-chloro-1,3-diols, 2-substituted 1,2,3-triols, 2-substituted serinols, and meso primary 1,4-diols, providing enantioenriched esters characterized by challenging acyclic tetrasubstituted carbon stereocenters. Partnered by one- or two-step follow-up transformations, this reaction provides a convenient and practical strategy for the rapid preparation of chiral C3 building blocks from readily available alcohols, particularly the industrially relevant glycerol. Mechanistic studies supported the proposed C-O bond coupling of acyl radicals.

A humanized 4-1BB-targeting agonistic antibody exerts potent antitumor activity in colorectal cancer without systemic toxicity.

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies and the patient survival rate remains unacceptably low. The anti-programmed cell death-1 (PD-1)/programmed cell death ligand 1 (PD-L1) antibody-based immune checkpoint inhibitors have been added to CRC treatment regimens, however, only a fraction of patients benefits. As an important co-stimulatory molecule, 4-1BB/CD137 is mainly expressed on the surface of immune cells including T and natural killer (NK) cells. Several agonistic molecules targeting 4-1BB have been clinically unsuccessful due to systemic toxicity or weak antitumor effects. We generated a humanized anti-4-1BB IgG4 antibody, HuB6, directed against a unique epitope and hypothesized that it would promote antitumor immunity with high safety. METHODS: The antigen binding specificity, affinity and activity of HuB6 were determined by enzyme-linked immunosorbent assay (ELISA), surface plasmon resonance (SPR), biolayer interferometry (BLI) and flow cytometry. The antitumor effects were evaluated in humanized mice bearing syngeneic tumors, and possible toxicity was evaluated in humanized mice and cynomolgus monkeys. RESULTS: HuB6 showed high specificity and affinity for a binding epitope distinct from those of other known 4-1BB agonists, including utomilumab and urelumab, and induced CD8 + T, CD4 + T and NK cell stimulation dependent on Fcγ receptor (FcγR) crosslinking. HuB6 inhibited CRC tumor growth in a dose-dependent manner, and the antitumor effect was similar with urelumab and utomilumab in humanized mouse models of syngeneic CRC. Furthermore, HuB6 combined with an anti-PD-L1 antibody significantly inhibited CRC growth in vivo. Additionally, HuB6 induced antitumor immune memory in tumor model mice rechallenged with 4 × 106 tumor cells. Toxicology data for humanized 4-1BB mice and cynomolgus monkeys showed that HuB6 could be tolerated up to a 180 mg/kg dose without systemic toxicity. CONCLUSIONS: This study demonstrated that HuB6 should be a suitable candidate for further clinical development and a potential agent for CRC immunotherapy.

Study on the controlled release and synergistic anti-oxidant activity in vitro and ex vivo of ligustrazine hydrochloride encapsulated into liposomes.

Ligustrazine with good antioxidant activity is one of the main active components of chuanxiong. We designed ligustrazine hydrochloride-loaded liposomes (LTH-L) by the thin film dispersion method. The particle size and zeta potential of liposomes was 118±10.61nm and -39.3±3.7mV, entrapment efficiency (EE%) was 75.05±10.67%. In vitro permeation across the dialysis membrane, the release rate (R%) of ligustrazine hydrochloride (LTH) and LTH-L were reached 80% and 60%. Ex Vivo transdermal behavior experiment showed the R% of LTH and LTH-L were between 30%-40%, the R% of LTH-L was slightly lower, because liposomes played the role on the sustained and controlled release of LTH. In addition, LTH, LTH-L and BL reacted with 2,2-diphenyl-1-picrylhydrazyl (DPPH) solution for two hours, the scavenge rates (SR%) were 55.06±2.73%, 11.3±0.03% and 37.25±1.12% respectively (P<0.001) and the SR% of LTH, LTH-L and BL reacted with H2O2 were 4.13±0.02%, 0.52±0.01% and 75.15±6.10%. The inhibit rate (IR%) of LTH, LTH-L and BL on malondialdehyde (MDA) in liver homogenate were 35.44±1.79%, 1.22±0.01% and 17.92±0.29% (P<0.001), the IR% were 30.82±0.93%, 1.7±0.01% and 25.19±0.60% (P<0.001) in anti-low density lipoprotein (LDL) oxidation experiments, perhaps LTH prepared into LTH-L can play a better antioxidant role.

Quantitation of low concentrations of polysorbates 80 in protein formulations by Coomassie brilliant blue.

Polysorbate 80, as pharmaceutical excipient and virus inactivating agent, is commonly used in the protein pharmaceutical industry. In this study, a method has been developed for the determination of low concentration of Polysorbate 80 in the presence of high concentration proteins (≤100 mg/ml) and excipients. This colorimetric method is based on the interaction of Polysorbate 80 and Coomassie brilliant blue, and suitable for quantitation of Polysorbate 80 in the range of 10-100 µg/ml. Dozens or hundreds of samples can be quantified simultaneously by using microplate. Besides Polysorbate 80, this method can also be used to determine other types of surfactants in protein solutions, such as Polysorbate 20, Triton X-100, NP40, SDS, Benzalkonium chloride/bromide and PEG4000.

The Controlled Release and Anti-Inflammatory Activity of a Tetramethylpyrazine-Loaded Thermosensitive Poloxamer Hydrogel.

PURPOSE: Tetramethylpyrazine-loaded poloxamer hydrogel materials were studied to achieve the controlled release of tetramethylpyrazine. METHODS: First, hydrogels having different concentrations of poloxamer 407 and poloxamer 188 were prepared. The gelling temperature and viscosity were measured. Second, we investigated the tetramethylpyrazine release rate from the thermosensitive poloxamer hydrogel materials in vitro and ex vivo. Finally, further study of the pharmacological efficacy of the tetramethylpyrazine-loaded thermosensitive poloxamer hydrogel materials was also investigated in vivo. RESULTS: The in vitro, ex vivo and in vivo experimental results showed that the tetramethylpyrazine-loaded poloxamer hydrogel with the appropriate gelling temperature, good adhesion and easy preparation controlled the release of tetramethylpyrazine. CONCLUSIONS: The hydrogel with the suitable nasal temperature and a satisfactory adhesion was selected. The relevant tests were carried out, including the determination of the concentration of drugs in the brain homogenate and the anti-inflammatory test after different modes of administration. So the poloxamer hydrogel was a novel carrier to deliver TMP to pass across the blood brain barrier via nasal administration.

[Expression of the Fra-1 gene in the peripheral blood of children with Wilms tumor].

OBJECTIVE: To study the expression of the Fra-1 gene in the peripheral blood of children with Wilms tumor and its clinical significance. METHODS: Fifty children pathologically diagnosed with Wilms tumor between December 2012 and January 2018 were enrolled as the case group, and 40 healthy children for physical examination were selected as the control group. Among the 45 children with Wilms tumor who were followed up, the children with continuous remission were included in the ideal efficacy group (n=33), and those with recurrence, metastasis or death were included in the poor efficacy group (n=12). Peripheral blood samples were collected from all subjects. Quantitative real-time PCR was used to measure the mRNA expression of Fra-1. RESULTS: The case group had significantly higher mRNA expression of Fra-1 in peripheral blood than the control group (P<0.05). In the case group, Fra-1 mRNA expression was significantly different between the individuals with and without distant metastasis and those with different TNM stages (P<0.05), but was not significantly different between the individuals with different sexes, ages, tumor diabetes, tumor locations and alpha-fetoprotein levels (P>0.05). The mRNA expression of Fra-1 was significantly lower in the ideal efficacy group than in the poor efficacy group (P<0.05). CONCLUSIONS: Fra-1 may be involved in the development of Wilms tumor and plays a certain role in its development, invasion and metastasis, but the mechanism remains to be further studied.

Synthesis of γ-Lactams by Mild, o-Benzoquinone-Induced Oxidation of Pyrrolidines Containing Oxidation-Sensitive Functional Groups.

The late-stage oxidation of substituted pyrrolidines offers good flexibility for the construction of γ-lactam libraries, and especially in recent years the methods for functionalization of pyrrolidine have been available. We reported a new strategy for oxidation of pyrrolidines to γ-lactams: reaction of pyrrolidine with an o-benzoquinone gives an N,O-acetal by direct oxidation of the α-C-H bond of the pyrrolidine ring, and then the N,O-acetal is further oxidized by the o-benzoquinone to the γ-lactam. Because the first oxidation occurs selectively at the α-C-H of the pyrrolidine ring, oxidation-sensitive functional groups (allyl-, vinyl-, hydroxyl-, and amino groups) on pyrrolidine ring are unaffected. The synthetic utility of this novel method was demonstrated by the facile syntheses of (S)-vigabatrin and two analogues.

Tetramethylpyrazine-Loaded Hydrogels: Preparation, Penetration Through a Subcutaneous-Mucous-Membrane Model, and a Molecular Dynamics Simulation.

Tetramethylpyrazine (TMP) was extracted from Ligusticum chuanxiong hort. The compound is known to have a variety of medicinal functions; in particular, it is used for the treatment of cerebral ischemic diseases. TMP-loaded hydrogels offer an excellent preparation with the capacity to bypass the blood-brain barrier, allowing treatment of the brain through intranasal administration. We prepared TMP-loaded hydrogels using carbomer 940 and evaluated the release of TMP from the hydrogel. We determined the release rate using Franz-type diffusion cell experiments with a subcutaneous-mucous-membrane model and also by a molecular dynamics (MD) simulation. In general, the former method was more complicated than the latter was. The dynamic behavior of TMP release from the hydrogel was revealed by analysis of the mean square displacement of the trajectory in the MD simulation. The coefficient of TMP diffusion from the hydrogel was calculated at different temperatures (277, 298, and 310 K) by using MD software. The results showed that the coefficient of diffusion increased with an increase in temperature. This trend was observed both experimentally and in the MD simulation. Therefore, the MD simulation was a complementary method to verify the experimental data.

Achiral Pyridine Ligand-Enabled Enantioselective Radical Oxytrifluoromethylation of Alkenes with Alcohols.

A conceptually novel strategy with achiral pyridine as the ancillary ligand to stabilize high-valent copper species for the first asymmetric radical oxytrifluoromethylation of alkenes with alcohols under CuI /phosphoric acid dual-catalysis has been developed. The transformation features mild reaction conditions, a remarkably broad substrate scope and excellent functional group tolerance, offering an efficient approach to a wide range of trifluoromethyl-substituted tetrahydrofurans bearing an α-tertiary stereocenter with excellent enantioselectivity. Mechanistic studies support the presumed role of the achiral pyridine as a coordinative ligand on copper metal to stabilize the key transient reaction species involved in the asymmetric induction process.

Rapid method for protein quantitation by Bradford assay after elimination of the interference of polysorbate 80.

Bradford assay is one of the most common methods for measuring protein concentrations. However, some pharmaceutical excipients, such as detergents, interfere with Bradford assay even at low concentrations. Protein precipitation can be used to overcome sample incompatibility with protein quantitation. But the rate of protein recovery caused by acetone precipitation is only about 70%. In this study, we found that sucrose not only could increase the rate of protein recovery after 1 h acetone precipitation, but also did not interfere with Bradford assay. So we developed a method for rapid protein quantitation in protein drugs even if they contained interfering substances.

Effect of impacted mandibular third molar extraction on periodontal microbiota and clinical parameters of adjacent teeth: A randomized clinical trial.

It is urgently necessary to clarify the effect of extraction of impacted mandibular third molar (IMTM) on the periodontal tissue of adjacent second molars (ASMs). In this study, the ASM periodontal condition and pathogenic microbes were assessed before IMTM extraction and at 1, 4, 8 and 12 weeks postoperatively. Based on the inclusion and exclusion criteria, our study revealed that IMTM extractions adversely affected distal － periodontal probing depth (dPPD), attachment loss (dAL), plaque index (dPLI) and bleeding on probing (dBOP) within 8 weeks, but these indices gradually normalize after 12 weeks. The subgingival pathogens near the ASMs distal surface, Porphyromonas and Pseudomonas, were significantly increased postoperatively. Moreover, relevance of ASMs clinical indices and subgingival microbes after IMTM extractions was found. In contrast to the situation in chronic periodontitis, the effects of IMTM extraction on dPPD, dAL, dPLI and dBOP of ASMs were mainly correlated with Pseudomonas. Additionally, while the IMTM extractions have adverse distal periodontal indices of ASMs within 8 weeks and increase subgingival pathogens, the modified triangular flap (MTF) had fewer distal periodontal indices and less Pseudomonas. Compared to the traditional envelope flap and triangular flap, the MTF benefits the periodontal health, which could be considered as the priority option for IMTM extractions.

The Effect of Arthroscopic Extra-Articular Entire Coracohumeral Ligament Release for Patients with Recalcitrant Frozen Shoulder.

OBJECTIVE: The thickened coracohumeral ligament (CHL) is an important part of the typical manifestations and magnetic resonance imaging of frozen shoulder. However, only a few clinical studies with limited cases on arthroscopic extra-articular entire CHL release exist in the literature. This study was to evaluate the effect of arthroscopic extra-articular entire CHL release for patients with recalcitrant frozen shoulder. METHODS: From February 2014 to February 2020, 81 cases of recalcitrant frozen shoulder patients treated with surgery in a single-center shoulder department and followed for more than 2 years were analyzed. Arthroscopic 360° capsular release was performed with intra-articular partial release (IPR group) or additional extra-articular entire release (IPR + EER group) of CHL. The same rehabilitation program was performed after surgery in both groups. Visual analogue scale (VAS) for pain, range of motion (ROM), and the Constant-Murley scoring system was evaluated before operation, at 3 months after operation, 6 months after operation, and the final follow-up. T-test, Mann-Whitney U-test and chi-squared test were used to compared data. RESULTS: There were 39 patients in the IPR group, with an average follow-up of 29.2 months. A total of Forty-two patients in the IPR + EER group completed a mean follow-up of 25.7 months. All incisions healed in stages. There were significant differences in Constant-Murley shoulder score, VAS score, and ROM before operation and at the final follow-up in both groups (both P < 0.001). The VAS score of the IPR + EER group was lower than that of the IPR group at 3 months after surgery (P < 0.05), and 6 months after operation (P < 0.05). External rotation, internal rotation, and abduction of ROMs and Constant-Murley shoulder score were significantly greater in the IPR + EER group at 3 months (P < 0.001, P < 0.05, P < 0.001, P < 0.05, respectively) and 6 months after operation (P < 0.001, P < 0.05, P < 0.001, P < 0.05, respectively). At the last follow-up, there was no significant difference in forward flexion, internal rotation, and abduction of ROMs, VAS, and the Constant-Murley shoulder score between the IPR and IPR + EER groups. The external rotation of the IPR + EER group was still greater than that of the IPR group at the last follow-up (P < 0.001). CONCLUSION: Arthroscopic extra-articular entire coracohumeral ligament release could solve early pain of shoulder joint, recover shoulder joint functions effectively, and achieve a satisfactory efficacy in the treatment of recalcitrant frozen shoulder.

Extraction of high inverted mesiodentes via the labial, palatal and subperiostal intranasal approach：A clinical prospective study.

The aim of this study is to provide criteria for the choice of the surgical approach for extraction of high inverted mesiodens. The operation statistics, life quality of postoperative patients, and the operative injury/recovery were compared and analysed. The laser Doppler blood flowmetry, laser speckle contrast imaging, and electric pulp testing were explored to detect the postoperative pulp and gingiva blood supply of adjacent teeth. For the clinician's primary concerns, the surgical time, the volume of osteotomy, and the amount of bleeding in the labial approach group (The p values are 0.0001, <0.0001, and 0.0131, respectively.) and intranasal approach group (All p values were <0.0001.) were significantly less than that in the palatal approach group. However, from the patient's perspective, the postoperative swelling in the labial approach was far more than that in the intranasal approach group (p =0.0044), with unsurprisingly lower satisfaction (p <0.0001). There were no significant differences in pulp and gingival blood supply of adjacent teeth and jaw development. Trauma was manageable in all patients. Within the limitations of the study it seems that extraction of mesiodens by the intranasal approach achieves a delicate balance between reducing surgical trauma and optimizing postoperative recovery.

Effects of modified triangular flap for third molar extraction on distal periodontal health of second molar: A randomized controlled study.

Objective: The aim of this study was to assess the effect of flap design for impacted mandibular third molar extraction on the distal periodontal tissue of their neighbors clinically, immunologically, and microbiologically. Study design: This randomized controlled study comprised 100 patients who were allocated randomly to receive either a triangular flap or a modified triangular flap. The distal periodontal pocket depth, plaque index, bleeding on probing, the presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia, and the level of interleukin-1ß, interleukin-8 and matrix metalloproteinase-8 of adjacent second molars were measured at baseline, and 1, 4 and 8 weeks after surgery. Results: After 1 and 4 weeks, distal periodontal conditions of adjacent second molars deteriorated, along with an increase in subgingival microbiota and inflammatory factors in both groups. And compared to the modified triangular flap group, the triangular flap group significantly increased (p < 0.05). Prevotella intermedia, interleukin-1ß and probing depth were positively correlated in both groups. After 8 weeks, they returned to the preoperative level. Conclusions: In this study, both flap designs for impacted mandibular third molar extractions was associated with worse clinical periodontal indices, increased inflammatory biomarkers of gingival crevicular fluid, and more subgingival pathogenic microbiota within 4 weeks. But compared with the triangular flap, the modified triangular flap was better for distal periodontal health of adjacent second molars, which provides certain directions for clinical treatment.

Design and Evaluation of Paeonol-Loaded Liposomes in Thermoreversible Gels for Atopic Dermatitis.

Paeonol (PAE) is a hydrophobic drug. In this study, we encapsulated paeonol in a lipid bilayer of liposomes (PAE-L), which delayed drug release and increased drug solubility. When PAE-L was dispersed in gels (PAE-L-G) based on a poloxamer matrix material for local transdermal delivery, we observed amphiphilicity, reversible thermal responsiveness, and micellar self-assembly behavior. These gels can be used for atopic dermatitis (AD), an inflammatory skin disease, to change the surface temperature of the skin. In this study, we prepared PAE-L-G at an appropriate temperature for the treatment of AD. We then assessed the gel's relevant physicochemical properties, in vitro cumulative drug release, and antioxidant properties. We found that PAE-loaded liposomes could be designed to increase the drug effect of thermoreversible gels. At 32 °C, PAE-L-G could change from solution state to gelatinous state at 31.70 ± 0.42 s, while the viscosity was 136.98 ± 0.78 MPa.S and the free radical scavenging rates on DPPH and H2O2 were 92.24 ± 5.57% and 92.12 ± 2.71%, respectively. Drug release across the extracorporeal dialysis membrane reached 41.76 ± 3.78%. In AD-like mice, PAE-L-G could also relieve skin damage by the 12th day. In summary, PAE-L-G could play an antioxidant role and relieve inflammation caused by oxidative stress in AD.

The novel delivery-exosome application for diagnosis and treatment of rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic degenerative disease characterized by persistent systemic synovitis, with a high risk of stiffness, pain, and swelling. It may affect the other extra-articular tissues. There is no ideal treatment for this disease at present, and it can only be controlled by medication to alleviate the prognosis. Exosomes are small vesicles secreted by various cells in the organism under normal or pathological conditions, and play a role in immune response, antigen presentation, cell migration, cell differentiation, tumor invasion and so on. Due to the adverse effects of conventional drugs and treatments in the treatment of RA, exosomes, as a nanocarrier with many advantages, can have a great impact on the loading of drugs for the treatment of RA. This article reviews the role of exosomes in the pathogenesis of RA and the progress of exosome-based therapy for RA.

Cu-catalysed enantioselective radical heteroatomic S-O cross-coupling.

The transition-metal-catalysed cross-coupling reaction has established itself as one of the most reliable and practical synthetic tools for the efficient construction of carbon-carbon/heteroatom (p-block elements other than carbon) bonds in both racemic and enantioselective manners. In contrast, development of the corresponding heteroatom-heteroatom cross-couplings has so far remained elusive, probably due to the under-investigated and often challenging heteroatom-heteroatom reductive elimination. Here we demonstrate the use of single-electron reductive elimination as a strategy for developing enantioselective S-O coupling under Cu catalysis, based on both experimental and theoretical results. The reaction manifests its synthetic potential by the ready preparation of challenging chiral alcohols featuring congested stereocentres, the expedient valorization of the biomass-derived feedstock glycerol, and the remarkable catalytic 4,6-desymmetrization of inositol. These results demonstrate the potential of enantioselective radical heteroatomic cross-coupling as a general chiral heteroatom-heteroatom formation strategy.

In Vitro Evaluation of Kaempferol-Loaded Hydrogel as pH-Sensitive Drug Delivery Systems.

The purpose of this study was to prepare and evaluate kaempferol-loaded carbopol polymer (acrylic acid) hydrogel, investigate its antioxidant activity in vitro, and compare the effects on drug release under different pH conditions. Drug release studies were conducted in three different pH media (pH 3.4, 5.4, and 7.4). The kaempferol-loaded hydrogel was prepared by using carbopol 934 as the hydrogel matrix. The morphology and viscosity of the preparation were tested to understand the fluidity of the hydrogel. The antioxidant activity of the preparation was studied by scavenging hydrogen peroxide and 2,2-diphenyl-1-picrilhidrazil (DPPH) radicals in vitro and inhibiting the production of malondialdehyde in mouse tissues. The results showed that kaempferol and its preparations had high antioxidant activity. In vitro release studies showed that the drug release at pH 3.4, 5.4, and 7.4 was 27.32 ± 3.49%, 70.89 ± 8.91%, and 87.9 ± 10.13%, respectively. Kaempferol-loaded carbopol hydrogel displayed greater swelling and drug release at higher pH values (pH 7.4).