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www.benisonmedia.com  ARTICLE  metabolic fuel.  PFK, plays a special role.   escalates or resolves.

 Think Grain Think Feed - Volume 11 | Issue 12 | Oct 2025




 Instead of only working in
 The Pentose Phosphate
 Phosphofructokinase (PFK)
 the cytoplasm, PK can
 Pathway: Fuelling ROS and
 catalyzes the key
 commitment step of
 where it binds to hypoxia-
 glycolysis. Increased PFK
 The pentose phosphate
 activity drives glucose   translocate into the nucleus,   Inflammation
 inducible factor 1-alpha (HIF-
 pathway (PPP), which
 deeper into the pathway,   1α). This complex enhances   branches off from glycolysis,
 sustaining rapid energy   transcription of pro-  is also reprogrammed in
 production. Under stress   inflammatory cytokines,   mastitis. In activated
 conditions such as hypoxia   particularly interleukin-1β   macrophages, PPP activity
 or oxidative stress,   (IL-1β) (Krawczyk et al., 2010;   increases, producing NADPH
 upregulation of PFK activity   Rodríguez-Prados et al.,   (Yu et al., 2019). NADPH
 promotes a metabolic shift   2010; Liu et al., 2022).   drives NADPH oxidases,
 toward anaerobic glycolysis,   The TCA Cycle Stalls and   which generate reactive
 ensuring continued ATP   Makes Trouble  oxygen species (ROS). While
 production when   Under normal conditions,   ROS are essential for
 mitochondrial oxidative   pyruvate from glycolysis is   bacterial killing, their
 phosphorylation is impaired.   fed into the TCA cycle,   overproduction damages
 This metabolic plasticity is   producing a steady supply of   mammary tissue and
 particularly important in   energy. But mastitis disrupts   prolongs inflammation (Saito
 rapidly dividing cells,   this cycle, leading to   et al., 2021; Ushio-Fukai et
 including tumour cells and   metabolic bottlenecks that   al., 2021).
 proliferating follicular cells.   generate inflammatory   Dysbiosis in the gut has
 A central regulator of this   metabolites.  similarly been associated
 step is PFKFB3, which   Succinate accumulates when   with PPP upregulation,
 produces fructose-2,6-  the cycle is impaired.   linking gastrointestinal
 bisphosphate, a potent   Succinate acts as a pro-  microbial imbalance to
 allosteric activator of PFK. In   inflammatory metabolite,   mastitis at the immune-
 mastitis, PFKFB3 expression   stabilizing HIF-1α and   metabolic interface (Horst et
 in mammary cells is elevated,  promoting sustained IL-1β   al., 2021; Kheirandish et al.,
 and its inhibition has been   production (Tannahill et al.,   2022).
 shown to reduce reactive   2013; Mills & O'Neill, 2014).   At the same time, the PPP
 oxygen species generation,   Itaconate is produced as an   contributes to antioxidant
 suppress HIF-1α signalling,   alternative pathway product.   defence. Sedoheptulose
 and alleviate Staphylococcus   Itaconate has direct   kinase (Shpk), a unique
 aureus-induced   antibacterial effects against   enzyme of this pathway,
 inflammation, underscoring   pathogens such as   generates sedoheptulose-7-
 its importance as both a   Mycobacterium tuberculosis   phosphate, which supports
 metabolic driver and a   and also reduces   NADH production and
 potential therapeutic target   inflammation by activating   enhances cellular antioxidant
 (Gao et al., 2024), as shown   the Nrf2 pathway and   capacity (Haschemi et al.,
 in Fig.1. Targeting glycolytic   restraining type I interferon   2012; Nagy & Haschemi,
 regulators has therefore   responses (Michelucci et al.,   2015). These findings
 emerged as a promising   2013; Mills et al., 2018). Thus,   emphasize the dual nature of
 strategy to control this   the TCA cycle doesn't just   the PPP: depending on
 metabolic overactivation.  slow down in mastitis but   context, it can exacerbate
 Pyruvate kinase (PK),   also actively shapes whether   oxidative stress and
 produced downstream of   the immune response
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