Valproic Acid Inhibits Ferroptosis and Improves Bone Integration in OVX Rats Through the AMPK/SIRT1 Pathway.

Parkinson's disease (PD) is a prevalent neurodegenerative disorder with an increasing incidence. PD is characterized by hallmark motor symptoms, including bradykinesia, rigidity, resting tremor, and postural instability. In advanced PD, when levodopa-induced dyskinesias, wearing-off and other complications emerge, deep brain stimulation (DBS) serves as an effective therapeutic option. Efforts to optimize DBS have explored various strategies, broadly categorized as: (1) modification of the stimulation target or site, including directional stimulation, and (2) modification of stimulation parameters and paradigms. As a result of ongoing optimization efforts, burst stimulation has emerged as a promising DBS approach to enhance therapeutic efficacy. Unlike conventional DBS (cDBS), which is characterized by continuous stimulation, burst stimulation consists of trains of electrical pulses interspersed with quiescent intervals. Each active stimulation period is known as the burst interval, while the non-stimulation phase is referred to as the pause interval. Within each burst interval, pulses are delivered at a defined intraburst frequency, whereas the interburst frequency determines the rate at which burst intervals occur (). These combined intervals can be delivered continuously (most burst paradigms) or intermittently (intermittent burst DBS). Unlike adaptive DBS, which continuously adjusts stimulation based on neural feedback, or variable frequency stimulation, which continuously changes pulse timing, burst stimulation delivers pulses at structured burst and pause intervals with specific intraburst frequency. Different burst patterns. An overview of the different burst patterns described in the literature is presented. Burst interval represents the period of stimulation of a single burst and pause interval represents the period of quiescence in between bursts. Intraburst frequency is defined as the frequency of stimulation pulses within a single burst and interburst frequency presents the repetition frequency of bursts. In coordinated reset stimulation shuffle time is the period after which the order of stimulated contacts is changed. BI: burst interval; PI: pause interval; intraF: intraburst frequency; interF: interburst frequency; cDBS: conventional, continuous deep brain stimulation; TBS: theta burst stimulation; BC: burst cycling stimulation; iBS: intermittent burst stimulation; C0/1/2: stimulation contacts; CR: coordinated reset; sCR: shuffled coordinated reset.