OBJECTIVE To explore the improvement effect and mechanism of salidroside on radiation-induced parotid gland injury in rats. METHODS Rats were randomly assigned into normal group， radiation group， salidroside low-dose （salidroside-L， 50 mg/kg） group， salidroside high-dose （salidroside-H， 100 mg/kg） group， and salidroside-H+inhibitor （100 mg/kg salidroside+0.1 µmol/kg H-89） group， with 10 rats in each group. Except for the normal group， rats in the other groups were subjected to radiation exposure to establish a model of radiation-induced parotid gland injury. Rats in each group were intraperitoneally injected with the corresponding drug or normal saline， once a day， for 40 consecutive days. After the last administration， the levels of reactive oxygen species （ROS）， cyclic adenosine monophosphate （cAMP）， superoxide dismutase （SOD）， and amylase in serum were detected； the pathological changes of parotid gland tissue were observed； the apoptosis rate of parotid gland tissue cells， the expression levels of B-cell lymphoma-2 （Bcl-2） and its associated X protein （Bax）， mRNA expression levels of interleukin-6 （IL- 6） and tumor necrosis factor-α （TNF-α）， the protein expression levels of type Ⅲ collagen （Col Ⅲ）， vasoactive intestinal peptide （VIP）， and the phosphorylation level of protein kinase A （PKA） in parotid gland tissue were determined. RESULTS Compared with normal group， the levels of ROS， amylase， apoptosis rate， Bax expression level， mRNA expression levels of IL-6 and TNF- α， and protein expression level of Col Ⅲ in the radiation group were significantly increased， while the levels of cAMP， SOD， Bcl-2 expression level， VIP protein expression level and PKA phosphorylation level were significantly decreased （P＜0.05）. Compared with radiation group， the above indicators in the salidroside-L group and salidroside-H group were significantly improved （P＜0.05）， and the improvement in the salidroside-H group was more significant （P＜0.05）； inhibitor H-89 significantly reversed the changes in the above indicators of the salidroside-H group （P＜0.05）. CONCLUSIONS Salidroside can effectively alleviate radiation-induced parotid gland injury in rats， and its mechanism may be related to the activation of the VIP-cAMP pathway.

More than 300 million people world-wide suffer from asthma,and the incidence is in-creasing year by year.As one of the most common chronic diseases,asthma is an immune-mediated inflammatory disease with complex triggering mechanisms and strong heterogeneity.With the in-depth study of physiological and pathological mech-anisms,therapeutic small molecule and hormone drugs have been introduced to control and treat most patients,but about 5％-10％of patients still suffer from various subtypes of difficult to control and treat asthma,that is,severe asthma.In the past decade,with the rapid development of bio-pharmaceutical research,protein and antibody have become the key drugs for the treatment of se-vere asthma with high efficacy,high specificity and high safety.However,biological drugs are usually administered by injection,they cannot be noninva-sive and directly delivered into the lung to quickly absorb and take effect.Therefore,there is an ur-gent need for the introduction of inhaled biologics with quick effectiveness,convenience,economy and safety in clinical.The review summarizes the existing small molecule,hormone and biological therapy drugs,and summarizes the development of inhalable biological agents of asthma,and ana-lyzes the future prospects of the inhalable biologi-cal drugs,which is designed to deepen the percep-tion of the direction of the inhalable biological drugs research,and update the information of the field,in order to provide reference for the develop-ment of more inhalable biologics.

More than 300 million people worldwide suffer from asthma, and the incidence is increasing year by year. As one of the most common chronic diseases, asthma is an immune-mediated inflammatory disease with complex triggering mechanisms and strong heterogeneity. With the in-depth study of physiological and pathological mechanisms, therapeutic small molecule and hormone drugs have been introduced to control and treat most patients, but about 5% - 10% of patients still suffer from various subtypes of difficult to control and treat asthma, that is, severe asthma. In the past decade, with the rapid development of bio-pharmaceutical research, protein and antibody have become the key drugs for the treatment of severe asthma with high efficacy, high specificity and high safety. However, biological drugs are usually administered by injection, they cannot be noninvasive and directly delivered into the lung to quickly absorb and take effect. Therefore, there is an urgent need for the introduction of inhaled biologics with quick effectiveness, convenience, economy and safety in clinical. The review summarizes the existing small molecule, hormone and biological therapy drugs, and summarizes the development of inhalable biological agents of asthma, and analyzes the future prospects of the inhalable biological drugs, which is designed to deepen the perception of the direction of the inhalable biological drugs research, and update the information of the field, in order to provide reference for the development of more inhalable biologics.

More than 300 million people world-wide suffer from asthma,and the incidence is in-creasing year by year.As one of the most common chronic diseases,asthma is an immune-mediated inflammatory disease with complex triggering mechanisms and strong heterogeneity.With the in-depth study of physiological and pathological mech-anisms,therapeutic small molecule and hormone drugs have been introduced to control and treat most patients,but about 5％-10％of patients still suffer from various subtypes of difficult to control and treat asthma,that is,severe asthma.In the past decade,with the rapid development of bio-pharmaceutical research,protein and antibody have become the key drugs for the treatment of se-vere asthma with high efficacy,high specificity and high safety.However,biological drugs are usually administered by injection,they cannot be noninva-sive and directly delivered into the lung to quickly absorb and take effect.Therefore,there is an ur-gent need for the introduction of inhaled biologics with quick effectiveness,convenience,economy and safety in clinical.The review summarizes the existing small molecule,hormone and biological therapy drugs,and summarizes the development of inhalable biological agents of asthma,and ana-lyzes the future prospects of the inhalable biologi-cal drugs,which is designed to deepen the percep-tion of the direction of the inhalable biological drugs research,and update the information of the field,in order to provide reference for the develop-ment of more inhalable biologics.

More than 300 million people world-wide suffer from asthma,and the incidence is in-creasing year by year.As one of the most common chronic diseases,asthma is an immune-mediated inflammatory disease with complex triggering mechanisms and strong heterogeneity.With the in-depth study of physiological and pathological mech-anisms,therapeutic small molecule and hormone drugs have been introduced to control and treat most patients,but about 5％-10％of patients still suffer from various subtypes of difficult to control and treat asthma,that is,severe asthma.In the past decade,with the rapid development of bio-pharmaceutical research,protein and antibody have become the key drugs for the treatment of se-vere asthma with high efficacy,high specificity and high safety.However,biological drugs are usually administered by injection,they cannot be noninva-sive and directly delivered into the lung to quickly absorb and take effect.Therefore,there is an ur-gent need for the introduction of inhaled biologics with quick effectiveness,convenience,economy and safety in clinical.The review summarizes the existing small molecule,hormone and biological therapy drugs,and summarizes the development of inhalable biological agents of asthma,and ana-lyzes the future prospects of the inhalable biologi-cal drugs,which is designed to deepen the percep-tion of the direction of the inhalable biological drugs research,and update the information of the field,in order to provide reference for the develop-ment of more inhalable biologics.

More than 300 million people world-wide suffer from asthma,and the incidence is in-creasing year by year.As one of the most common chronic diseases,asthma is an immune-mediated inflammatory disease with complex triggering mechanisms and strong heterogeneity.With the in-depth study of physiological and pathological mech-anisms,therapeutic small molecule and hormone drugs have been introduced to control and treat most patients,but about 5％-10％of patients still suffer from various subtypes of difficult to control and treat asthma,that is,severe asthma.In the past decade,with the rapid development of bio-pharmaceutical research,protein and antibody have become the key drugs for the treatment of se-vere asthma with high efficacy,high specificity and high safety.However,biological drugs are usually administered by injection,they cannot be noninva-sive and directly delivered into the lung to quickly absorb and take effect.Therefore,there is an ur-gent need for the introduction of inhaled biologics with quick effectiveness,convenience,economy and safety in clinical.The review summarizes the existing small molecule,hormone and biological therapy drugs,and summarizes the development of inhalable biological agents of asthma,and ana-lyzes the future prospects of the inhalable biologi-cal drugs,which is designed to deepen the percep-tion of the direction of the inhalable biological drugs research,and update the information of the field,in order to provide reference for the develop-ment of more inhalable biologics.

More than 300 million people world-wide suffer from asthma,and the incidence is in-creasing year by year.As one of the most common chronic diseases,asthma is an immune-mediated inflammatory disease with complex triggering mechanisms and strong heterogeneity.With the in-depth study of physiological and pathological mech-anisms,therapeutic small molecule and hormone drugs have been introduced to control and treat most patients,but about 5％-10％of patients still suffer from various subtypes of difficult to control and treat asthma,that is,severe asthma.In the past decade,with the rapid development of bio-pharmaceutical research,protein and antibody have become the key drugs for the treatment of se-vere asthma with high efficacy,high specificity and high safety.However,biological drugs are usually administered by injection,they cannot be noninva-sive and directly delivered into the lung to quickly absorb and take effect.Therefore,there is an ur-gent need for the introduction of inhaled biologics with quick effectiveness,convenience,economy and safety in clinical.The review summarizes the existing small molecule,hormone and biological therapy drugs,and summarizes the development of inhalable biological agents of asthma,and ana-lyzes the future prospects of the inhalable biologi-cal drugs,which is designed to deepen the percep-tion of the direction of the inhalable biological drugs research,and update the information of the field,in order to provide reference for the develop-ment of more inhalable biologics.

More than 300 million people world-wide suffer from asthma,and the incidence is in-creasing year by year.As one of the most common chronic diseases,asthma is an immune-mediated inflammatory disease with complex triggering mechanisms and strong heterogeneity.With the in-depth study of physiological and pathological mech-anisms,therapeutic small molecule and hormone drugs have been introduced to control and treat most patients,but about 5％-10％of patients still suffer from various subtypes of difficult to control and treat asthma,that is,severe asthma.In the past decade,with the rapid development of bio-pharmaceutical research,protein and antibody have become the key drugs for the treatment of se-vere asthma with high efficacy,high specificity and high safety.However,biological drugs are usually administered by injection,they cannot be noninva-sive and directly delivered into the lung to quickly absorb and take effect.Therefore,there is an ur-gent need for the introduction of inhaled biologics with quick effectiveness,convenience,economy and safety in clinical.The review summarizes the existing small molecule,hormone and biological therapy drugs,and summarizes the development of inhalable biological agents of asthma,and ana-lyzes the future prospects of the inhalable biologi-cal drugs,which is designed to deepen the percep-tion of the direction of the inhalable biological drugs research,and update the information of the field,in order to provide reference for the develop-ment of more inhalable biologics.

More than 300 million people world-wide suffer from asthma,and the incidence is in-creasing year by year.As one of the most common chronic diseases,asthma is an immune-mediated inflammatory disease with complex triggering mechanisms and strong heterogeneity.With the in-depth study of physiological and pathological mech-anisms,therapeutic small molecule and hormone drugs have been introduced to control and treat most patients,but about 5％-10％of patients still suffer from various subtypes of difficult to control and treat asthma,that is,severe asthma.In the past decade,with the rapid development of bio-pharmaceutical research,protein and antibody have become the key drugs for the treatment of se-vere asthma with high efficacy,high specificity and high safety.However,biological drugs are usually administered by injection,they cannot be noninva-sive and directly delivered into the lung to quickly absorb and take effect.Therefore,there is an ur-gent need for the introduction of inhaled biologics with quick effectiveness,convenience,economy and safety in clinical.The review summarizes the existing small molecule,hormone and biological therapy drugs,and summarizes the development of inhalable biological agents of asthma,and ana-lyzes the future prospects of the inhalable biologi-cal drugs,which is designed to deepen the percep-tion of the direction of the inhalable biological drugs research,and update the information of the field,in order to provide reference for the develop-ment of more inhalable biologics.

More than 300 million people world-wide suffer from asthma,and the incidence is in-creasing year by year.As one of the most common chronic diseases,asthma is an immune-mediated inflammatory disease with complex triggering mechanisms and strong heterogeneity.With the in-depth study of physiological and pathological mech-anisms,therapeutic small molecule and hormone drugs have been introduced to control and treat most patients,but about 5％-10％of patients still suffer from various subtypes of difficult to control and treat asthma,that is,severe asthma.In the past decade,with the rapid development of bio-pharmaceutical research,protein and antibody have become the key drugs for the treatment of se-vere asthma with high efficacy,high specificity and high safety.However,biological drugs are usually administered by injection,they cannot be noninva-sive and directly delivered into the lung to quickly absorb and take effect.Therefore,there is an ur-gent need for the introduction of inhaled biologics with quick effectiveness,convenience,economy and safety in clinical.The review summarizes the existing small molecule,hormone and biological therapy drugs,and summarizes the development of inhalable biological agents of asthma,and ana-lyzes the future prospects of the inhalable biologi-cal drugs,which is designed to deepen the percep-tion of the direction of the inhalable biological drugs research,and update the information of the field,in order to provide reference for the develop-ment of more inhalable biologics.