The 3D human brain organ is aninvitrocultured organ that can be implemented by a researcher in recent years in a standard tissue culture chamber. Its growth and development is very similar to the endogenous developmental program of the human brain. The 3D human brain organs can promote people's understanding of human brain characteristics, and thus, conduct more in-depth research on human brain neuropsychiatric diseases. This is a review of the development, application, obstacles and prospects of 3D human brain organs.

Stroke is a common cerebrovascular disease， characterized by high incidence， mortality and disability rate. Neuronal cells， the basic unit of the central nervous system， can be injured to varying degrees when stroke occurs. Neuronal cell injury after stroke is also the key cause leading to neurological dysfunction， affecting the prognosis and quality of life of patients. Therefore， reducing the neuronal cell injury and delaying the process of cell death are effective to decrease the nerve function injury in stroke patients and improve their prognosis， thus lowering the death and disability rate of stroke. Ferroptosis is a new form of cell death that has been widely concerned in recent years. Several studies have confirmed that there is ferroptosis in neuronal cells after stroke. Since ferroptosis is an adjustable form， its intervention can help regulate the injury and death of neuronal cells. Studies have shown that inhibiting ferroptosis plays a role in protecting neuronal cells. Traditional Chinese medicine （TCM）， with the multi-channel and multi-target treatment advantages， has been widely used in the whole stroke and has achieved good clinical efficacy. It might be a new direction taking TCM regulation of ferroptosis as the entry point for stroke treatment in the future. This review revealed the mechanism of ferroptosis， discussed the research status of TCM in intervening in neuronal cell ferroptosis， and provided reference for further improving the efficacy of TCM in stroke.

Central nervous system （CNS） is a sophisticated system subject to complex regulation， which dominates the high-level neural activities of the human body. Due to its complex physiological structure and refined regulatory mechanism covering a variety of diseases， CNS is the place where many chronic， refractory and rare diseases occur. Nerve cell is the basic unit of CNS， and its dysfunction and death is the root cause of CNS diseases. Ferroptosis is a new form of programmed cell death proposed in recent years， and has been proved to be closely related to the production and development of multiple CNS diseases. Traditional Chinese medicine （TCM）， including Chinese herbs， acupuncture and moxibustion， and massage， has shown unique advantages in the treatment of CNS diseases for a long time. A large number of studies have demonstrated that TCM participates in the regulation of CNS diseases via regulating ferroptosis and shows a good research prospect. This paper summarized the characteristics of ferroptosis and discussed the association between ferroptosis and CNS diseases in pathological mechanism. We also reviewed the regulation of various CNS diseases by different TCM interventions through ferroptosis， providing references for TCM to participate in the treatment of CNS diseases properly in the future.

Stroke is one of the most common cerebrovascular diseases， including hemorrhagic stroke and ischemic stroke. From a modern medical perspective， stroke is caused by cerebrovascular damage or embolism leading to impaired blood circulation. From the traditional Chinese medicine （TCM） perspective， the pathogenesis of this disease is mainly due to the disorder of Qi and blood， which ascend to the brain， causing either blood extravasation or blockage of brain collaterals. Stasis is a pathological factor that runs throughout the entire course of stroke， and the method of promoting blood circulation and resolving stasis has been a core treatment for stroke for a long time. Hirudo， as a traditional insect drug， has shown good effects in promoting blood circulation and resolving stasis. Modern pharmacological research has confirmed that Hirudo contains anticoagulant components， which provide significant advantages in dissolving thrombi in ischemic stroke and facilitating hematoma absorption in hemorrhagic stroke. Hirudo and its related preparations have been proven to exert an anti-stroke effect through anticoagulation， anti-thrombosis， and protection of vascular endothelium. As a result， they have been widely used in the treatment of stroke. This article explored the theoretical basis and research status of using Hirudo for treating stroke based on its main active components and hemostatic properties and summarized the current research status of commonly used Hirudo-based formulations and preparations， aiming to provide references for the involvement of Hirudo in stroke treatment.