As one of the most important biological drugs, protein and peptide drugs have been increasingly used in the prevention, diagnosis and treatment of diseases in recent years. However, most of them need to be injected and lack of long-acting formulations, which brings many troubles to patients suffering from chronic diseases. In this review, we summarized the strategies for engineering long-acting formulations for proteins and peptides via preparation means, including extended-release injection, implant, oral preparations and transdermal drug delivery systems, and analyzed their release mechanisms, research advances, advantages and shortcomings, thereby providing potential approaches for promoting the formulation improvement of these drugs.

BACKGROUND:The content of serum thrombin in patients with osteoarthritis is significantly higher than that in normal individuals,and thrombin can induce inflammatory degeneration of rat chondrocytes,suggesting that inhibiting the function of thrombin may become a method for treating osteoarthritis.Celecoxib is a common therapeutic drug for the clinical treatment of osteoarthritis.It is not yet known whether it improves chondrocyte degeneration by inhibiting the activity of thrombin. OBJECTIVE:To investigate the effect of celecoxib on thrombin-induced degeneration of rat chondrocytes. METHODS:Thrombin levels in the serum of osteoarthritis patients and normal individuals were detected by an ELISA kit.Primary chondrocytes of neonatal Sprague-Dawley rats were isolated,and all experiments were performed with cells from passage one.Chondrocytes were randomly divided into three groups:control group,thrombin group,and celecoxib group.The cell morphology of the three groups was observed under an inverted microscope,and an Edu kit was used to detect the cell proliferation.qRT-PCR was used to detect the expression of extracellular matrix components(aggrecan,elastin,cartilage oligomeric matrix proteins),inflammatory factors(interleukin-1,interleukin-6,and tumor necrosis factor-α),and chemokines(monocyte chemotactic protein 2,monocyte chemotactic protein 7,granulocyte chemotactic protein 6).The expression of type 2 collagen α1 was detected by immunofluorescence.Western blot method was used to detect the expression of catabolic metabolism genes,such as matrix metalloproteinase 9,matrix metalloproteinase 13,and cyclooxygenase 2. RESULTS AND CONCLUSION:Patients with osteoarthritis had higher levels of thrombin in the serum compared with normal individuals.Under the microscope,celecoxib was found to significantly inhibit fibroid changes in chondrocytes.Compared with the thrombin group,celecoxib inhibited the proliferation of chondrocytes.The downregulation of extracellular matrix gene expression,such as type II collagen α1,in the thrombin group was inhibited by celecoxib(P<0.05).Thrombin promoted the expression of inflammatory factors(interleukin-1,interleukin-6,and tumor necrosis factor-α),chemokines(monocyte chemotactic protein 2,monocyte chemotactic protein 7,granulocyte chemotactic protein 6),as well as catabolic genes(matrix metalloproteinase 9,matrix metalloproteinase 13,and cyclooxygenase 2),and under the intervention of celecoxib,the expression of these genes could be downregulated(P<0.05).Overall,these findings indicate that celecoxib inhibits the pro-inflammatory effects of thrombin and thereby ameliorates chondrocyte degeneration in rats.

Objective To investigate the relationship between coagulation indicators and early prognosis in patients with acute respiratory distress syndrome (ARDS).Methods The data of ARDS patients receiving the treatment in the intensive care unit (ICU) from 2008-2019 were selected from the Critical Care Medicine Open Database (MIMIC-Ⅳ V2.0 version) jointly published by MIT,Beth Israel Deaconess Medical Center,and Philips Medical,the data were categorized according to the severity of the patients' disease and the causes of lung damage.The coagulation indexes and 28 d mortality (m28d) rates were compared among different ARDS patients.The receiver operating characteristic (ROC) curve was drawn.The area under the curve was calculated to evaluate the predictive values of the related indicators.The univariate and multivariate logistic re-gression was adopted to analyze the risk factors affecting m28d in the patients with ARDS.Results Maximum prothrombin time (PTmax) in the patients with pulmonary origin ARDS was significantly lower than that in the patients without pulmonary origin ARDS,and the difference was statistically significant (P<0.05).PLTmin,PLTmax and Sequential Organ Failure Assessment (SOFA) score had statistical difference among dif-ferent severity degrees of ARDS patients (P<0.05).Minimum international normalized ratio (INRmin),maxi-mum international normalized ratio (INRmax),minimum prothrombin time (PTmin),PTmax,maximum activated partial thromboplastin time (APTTmax) and SOFA score had statistical differences between the survival group and death group (P<0.05).AUC of INRmin,INRmax,PTmin,PTmax and APTTmax were 0.607,0.624,0.610,0.620 and 0.648 respectively.The multivariate logistic regression analysis showed that APTTmax (OR=1.011,95%CI:1.001-1.022,P=0.029) was an independent risk factor for affecting m28d in the ARDS patients.Conclu-sion Plasma PLT levels in different severities of ARDS patients have the difference and APTTmax on the first day in ICU is an independent risk factor for affecting early prognosis in ARDS patients.

Objective:To investigate the effect of Qideng Mingmu capsule on the formation and remodeling of retinal neovascularization in mice with oxygen-induced retinopathy (OIR).Methods:Thirty-six postnatal day 7 (P7)SPF grade C57BL/6J pups were divided into normal group, OIR group, Qideng Mingmu capsule group and apatinib group by random number table method, with 9 mice in each group.The mice in the normal group were raised in normal environment.The mice in the other three groups were fed in hyperoxic environment of (75±2)% oxygen concentration for 5 days from P7 to P12 and then were fed in normal environment for 5 days from P12 to P17 to establish the OIR model.From P12, mice in Qideng Mingmu capsule group and apatinib group were given intragastric administration of Qideng Mingmu capsule (900 mg/kg) and vascular endothelial growth factor receptor 2 inhibitor apatinib (70 mg/kg) respectively, once a day for 5 consecutive days.On P17, paraffin sections of mouse eyeballs were made and stained with hematoxylin-eosin to count the number of vascular endothelial cells that broke through the internal limiting membrane.The retinal slices were prepared and stained with FITC-dextran to quantify the retinal non-perfusion area, neovascularization density and total vascular density.The distribution and fluorescence intensity of retinal vascular endothelial cell marker CD31 and pericyte marker α-smooth muscle actin (α-SMA) were observed by double immunofluorescence staining.Immunohistochemical staining was used to detect the expression and distribution of retinal hypoxia inducible factor-1α (HIF-1α) and vascular endothelial cadherin (VE-cadherin).The use and care of animals were in accordance with the Regulations on the Management of Laboratory Animals issued by the Ministry of Science and Technology.This study was approved by the Animal Ethics Committee of Chengdu University of Traditional Chinese Medicine (No.2019-30).Results:The number of vascular endothelial cells breaking through the internal limiting membrane in normal group, OIR group, Qideng Mingmu capsule group and apatinib group were (2.83±4.40), (37.33±5.43), (23.83±6.79) and (14.00±9.34), respectively, with a statistically significant overall difference ( F=28.313, P<0.001).There were more vascular endothelial cells breaking through internal limiting membrane in OIR group than in normal group, Qideng Mingmu capsule group and apatinib group, showing statistically significant differences (all at P<0.05).In the observation of mouse retinal slices, there were large non-perfusion areas, neovascularization buds and disordered distribution of blood vessels in OIR group.The distribution of blood vessels was more uniform and the areas of non-perfusion and neovascularization were smaller in Qideng Mingmu capsule group and apatinib group than in OIR group.The relative area of central retinal non-perfusion area and neovascularization density were significantly lower in normal group, Qideng Mingmu capsule group and apatinib group than in OIR group (all at P<0.05).The immunofluorescence intensity of CD31 and the absorbance value of HIF-1α were significantly lower, and the immunofluorescence intensity of α-SMA and the absorbance value of VE-cadherin were significantly higher in normal group, Qideng Mingmu capsule group and apatinib group than in OIR group (all at P<0.05). Conclusions:Qideng Mingmu capsule can inhibit retinal neovascularization formation, increase vascular pericyte coverage, relieve retinal hypoxia and increase vascular integrity in OIR mice.It can protect the retinal vessels of OIR mice.

Objective: To investigate the role of nucleotidebinding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome in hyperalgesia induced by temporomandibular joint osteoarthritis (TMJOA) in rats. Methods : Twenty 6-week-old male SD rats were randomly divided into NS group and MIA group．The rat model of TMJOA was established by injection monosodium iodoacetate ( MIA) into the upper cavity of temporomandibular joint (TMJ) ．The changes of pain threshold in the TMJ region of rats after MIA injection were detected by Von Frey．The changes of condyle structure were observed by Hematoxylin-eosin ( HE ) and Safranin O-fast green stains．Histopathological changes of trigeminal ganglion (TG) were observed by HE stains．The expression and distribution of TG NLRP3 protein were detected by immunohistochemistry．Western blot was used to detect the protein levels of NLRP3 and interleukin (IL) -1 β in TG．The mRNA levels of NLRP3，apoptosis-associated speck-like protein (ASC) ，cysteinyl aspartate specific proteinase ( Caspase-1) ，IL-1β and IL-18 in TG were detected by quantitative real-time polymerase chain reaction ( qRT-PCR) . Results : Compared to saline group，the pain threshold of experimental TMJ osteoarthritis rats decreased (P＜0. 05) ．TMJ and TG showed obvious pathological changes．The protein and mRNA levels of NLRP3 expressed in the tissues of rats in the TMJOA group increased (P ＜0. 05 ) . Conclusion NLRP3 inflammasome may be involved in the regulation of hyperalgesia in TMJOA rats.